~ubuntu-branches/debian/squeeze/maxima/squeeze

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html401/loose.dtd">
<html>
<!-- Created on April, 24 2010 by texi2html 1.76 -->
<!--
Written by: Lionel Cons <Lionel.Cons@cern.ch> (original author)
            Karl Berry  <karl@freefriends.org>
            Olaf Bachmann <obachman@mathematik.uni-kl.de>
            and many others.
Maintained by: Many creative people <dev@texi2html.cvshome.org>
Send bugs and suggestions to <users@texi2html.cvshome.org>

-->
<head>
<title>Maxima 5.21.1 Manual: 8. Plotting</title>

<meta name="description" content="Maxima 5.21.1 Manual: 8. Plotting">
<meta name="keywords" content="Maxima 5.21.1 Manual: 8. Plotting">
<meta name="resource-type" content="document">
<meta name="distribution" content="global">
<meta name="Generator" content="texi2html 1.76">
<meta http-equiv="Content-Type" content="text/html; charset=us-ascii">
<style type="text/css">
<!--
a.summary-letter {text-decoration: none}
pre.display {font-family: serif}
pre.format {font-family: serif}
pre.menu-comment {font-family: serif}
pre.menu-preformatted {font-family: serif}
pre.smalldisplay {font-family: serif; font-size: smaller}
pre.smallexample {font-size: smaller}
pre.smallformat {font-family: serif; font-size: smaller}
pre.smalllisp {font-size: smaller}
span.sansserif {font-family:sans-serif; font-weight:normal;}
ul.toc {list-style: none}
body
{
    color: black;
    background: white; 
    margin-left: 8%;
    margin-right: 13%;
}

h1
{
    margin-left: +8%;
    font-size: 150%;
    font-family: sans-serif
}

h2
{
    font-size: 125%;
    font-family: sans-serif
}

h3
{
    font-size: 100%;
    font-family: sans-serif
}

h2,h3,h4,h5,h6 { margin-left: +4%; }

div.textbox
{
    border: solid;
    border-width: thin;
    /* width: 100%; */
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em
}

div.titlebox
{
    border: none;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em;
    background: rgb(200,255,255);
    font-family: sans-serif
}

div.synopsisbox
{
    border: none;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 2em;
    padding-right: 2em;
     background: rgb(255,220,255);
    /*background: rgb(200,255,255); */
    /* font-family: fixed */
}

pre.example
{
    border: 1px solid gray;
    padding-top: 1em;
    padding-bottom: 1em;
    padding-left: 1em;
    padding-right: 1em;
    /* background: rgb(247,242,180); */ /* kind of sandy */
    /* background: rgb(200,255,255); */ /* sky blue */
    background-color: #F1F5F9; /* light blue-gray */
    /* font-family: "Lucida Console", monospace */
}

div.spacerbox
{
    border: none;
    padding-top: 2em;
    padding-bottom: 2em
}

div.image
{
    margin: 0;
    padding: 1em;
    text-align: center;
}

div.categorybox
{
    border: 1px solid gray;
    padding-top: 0px;
    padding-bottom: 0px;
    padding-left: 1em;
    padding-right: 1em;
    background: rgb(247,242,220);
}


-->
</style>

<link rel="icon" href="http://maxima.sourceforge.net/favicon.ico"/>
</head>

<body lang="en" bgcolor="#FFFFFF" text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000">

<a name="Plotting"></a>
<a name="SEC31"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="maxima_7.html#SEC30" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC32" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima_7.html#SEC29" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h1 class="chapter"> 8. Plotting </h1>

<table class="menu" border="0" cellspacing="0">
<tr><td align="left" valign="top"><a href="#SEC32">8.1 Introduction to Plotting</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top"><a href="#SEC33">8.2 Plotting Formats</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top"><a href="#SEC34">8.3 Functions and Variables for Plotting</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top"><a href="#SEC35">8.4 Plotting Options</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top"><a href="#SEC36">8.5 Gnuplot Options</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
<tr><td align="left" valign="top"><a href="#SEC37">8.6 Gnuplot_pipes Format Functions</a></td><td>&nbsp;&nbsp;</td><td align="left" valign="top">
</td></tr>
</table>

<p><a name="Item_003a-Introduction-to-Plotting"></a>
</p><hr size="6">
<a name="Introduction-to-Plotting"></a>
<a name="SEC32"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC31" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC33" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.1 Introduction to Plotting </h2>

<p>Maxima uses an external plotting package to make the plots (see the
section on Plotting formats). The plotting functions calculate a set of
points and pass them to the plotting package together with a set of
commands. That information can be passed to the external program either
through a pipe or by calling the program with the name of a file where
the data has been saved. The data file is given the name
<code>maxout.interface</code>, where <code>interface</code> is the name of the
plotting interface being used (gnuplot, xmaxima, mgnuplot or
gnuplot_pipes).
</p>
<p>The <code>maxout.interface</code> file, in the cases when it is used, is
created in the directory specified by the system variable
<var>maxima_tempdir</var>. That location can be changed; by assigning to that
variable a string that represents a valid directory where Maxima can
create new files.
</p>
<p>After a plot has been created, the file <code>maxout.interface</code> can be
executed again with the appropriate external program. If a Maxima plotting
command fails to show anything, that file can be inspected to look for
possible sources of problems.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


<p><a name="Item_003a-Plotting-Formats"></a>
</p><hr size="6">
<a name="Plotting-Formats"></a>
<a name="SEC33"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC32" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC34" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.2 Plotting Formats </h2>

<p>There are currently two external plotting programs that Maxima use: Gnuplot
and Xmaxima. There are various different formats for those programs,
which can be selected with the option <code>plot_format</code> (see
the Plotting Options section).
</p>
<p>The plotting formats are the following:
</p>
<ul>
<li>
<strong>gnuplot</strong> (default on Windows)

<p>Used to launch the external program gnuplot, which must be installed in
your system. All plotting commands and data are saved into the file
<code>maxout.gnuplot</code>.
</p>
</li><li>
<strong>gnuplot_pipes</strong> (default on non-Windows platforms)

<p>This format is not available in Windows platforms.
It is similar to the <code>gnuplot</code> format except that the commands are sent
to gnuplot through a pipe, while the data are saved into the file
<code>maxout.gnuplot_pipes</code>. A single gnuplot process is kept open
and subsequent plot commands will be sent to the same process, replacing
previous plots, unless the gnuplot pipe is closed with the function
<code>gnuplot_close()</code>. When this format is used, the function
<code>gnuplot_replot</code> can be used to modify a plot that has already
displayed on the screen (see <code>gnuplot_replot</code>).
</p>
<p>This format should only be used to plot to the
screen; for plotting to files it is better to use the <code>gnuplot</code>
format.
</p>
</li><li>
<strong>mgnuplot</strong>

<p>Mgnuplot is a Tk-based wrapper around gnuplot. It is included in the
Maxima distribution. Mgnuplot offers a rudimentary GUI for gnuplot,
but has fewer overall features than the plain gnuplot
interface. Mgnuplot requires an external gnuplot installation and, in
Unix systems, the Tcl/Tk system.
</p>
</li><li>
<strong>xmaxima</strong>

<p>Xmaxima is a Tcl/Tk graphical interface for Maxima that can also be used
to display plots created when Maxima is run from the console or from other
graphical interfaces. To use this format, the xmaxima program, which is
distributed together with Maxima, should be installed. If Maxima is
being run from xmaxima itself, this format will make the plot functions
send the data and commands through the same socket used for the
communication between Maxima and Xmaxima. When used from the console
or from other interface, the commands and data will be saved in the file
<code>maxout.xmaxima</code>, and the xmaxima program will be launched with the
name of the location of that file as argument.
</p>
<p>In previous versions this format used to be called <code>openmath</code>; that
old name will still be accepted as a synonym for <code>xmaxima</code>.
</p>
</li></ul>

<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


<p><a name="Item_003a-Functions-and-Variables-for-Plotting"></a>
</p><hr size="6">
<a name="Functions-and-Variables-for-Plotting"></a>
<a name="SEC34"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC33" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC35" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.3 Functions and Variables for Plotting </h2>

<p><a name="Item_003a-contour_005fplot"></a>
</p><dl>
<dt><u>Function:</u> <b>contour_plot</b><i> (<var>expr</var>, <var>x_range</var>, <var>y_range</var>, <var>options</var>, ...)</i>
<a name="IDX250"></a>
</dt>
<dd><p>It plots the contours (curves of equal value) of <var>expr</var>
over the region <var>x_range</var> by <var>y_range</var>.
Any additional arguments are treated the same as in <code>plot3d</code>.
</p>
<p>This function only works when the plot format is either <code>gnuplot</code>
or <code>gnuplot_pipes</code>. The additional package <code>implicit_plot</code> can
also be used to plot contours and it works for any format. See
<code>implicit_plot</code>.
</p>
<p>Examples:
</p>
<pre class="example">(%i1) contour_plot (x^2 + y^2, [x, -4, 4], [y, -4, 4])$
</pre>
<p><div class="image"><img src="./figures/contour1.gif" alt="figures/contour1"></div>
</p>
<pre class="example">(%i1) F(x, y) := x^3 + y^2;
                                   3    2
(%o1)                  F(x, y) := x  + y
(%i2) contour_plot (F, [u, -4, 4], [v, -4, 4])$
</pre>
<p><div class="image"><img src="./figures/contour2.gif" alt="figures/contour2"></div>
</p>
<p>You can add any options accepted by <code>plot3d</code>; for instance, the
option <code>legend</code> with a value of false, to remove the
legend. Gnuplot chooses, by default, 3 contours to show. to increase the
number of levels, it is necessary to specify a custom gnuplot preamble:
</p>
<pre class="example">(%i1) contour_plot (u^3 + v^2, [u, -4, 4], [v, -4, 4],
(%i2) [legend,false], [gnuplot_preamble,&quot;set cntrparam levels 12&quot;])$
</pre>
<p><div class="image"><img src="./figures/contour3.gif" alt="figures/contour3"></div>
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-get_005fplot_005foption"></a>
</p><dl>
<dt><u>Function:</u> <b>get_plot_option</b><i> (<var>keyword</var>, <var>index</var>)</i>
<a name="IDX251"></a>
</dt>
<dd><p>Returns a value of the option with name <var>keyword</var>, stored in the
global variable <code>plot_options</code>. A value of 1 for the index will
return the keyword itself; a value of 2 turn returns the first parameter
following the keyword, and so on.
</p>
<p>See also <code>plot_options</code>, <code>set_plot_option</code> and the section on
Plotting Options.
</p>
</dd></dl>

<p><a name="Item_003a-make_005ftransform"></a>
</p><dl>
<dt><u>Function:</u> <b>make_transform</b><i> ([<var>var1</var>, <var>var2</var>, <var>var3</var>], <var>fx</var>, <var>fy</var>, <var>fz</var>)</i>
<a name="IDX252"></a>
</dt>
<dd><p>Returns a function suitable to be used in the option <code>transform_xy</code>
of plot3d. The three variables <var>var1</var>, <var>var2</var>, <var>var3</var> are
three dummy variable names, which represent the 3 variables given by the
plot3d command (first the two independent variables and then the
function that depends on those two variables). The three functions
<var>fx</var>, <var>fy</var>, <var>fz</var> must depend only on those 3 variables, and
will give the corresponding x, y and z coordinates that should be
plotted. There are two transformations defined by default:
<code>polar_to_xy</code> and <code>spherical_to_xyz</code>; see the documentation
for those two transformations.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-polar_005fto_005fxy"></a>
</p><dl>
<dt><u>System function:</u> <b>polar_to_xy</b>
<a name="IDX253"></a>
</dt>
<dd><p>It can be given as value for the <code>transform_xy</code> option of
plot3d. Its effect will be to interpret the two independent variables in
plot3d as the distance from the z axis and the azimuthal angle (polar
coordinates), and transform them into x and y coordinates.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-plot2d"></a>
</p><dl>
<dt><u>Function:</u> <b>plot2d</b><i> (<var>plot</var>, <var>x_range</var>, ..., <var>options</var>, ...)</i>
<a name="IDX254"></a>
</dt>
<dt><u>Function:</u> <b>plot2d</b><i> ([<var>plot_1</var>, ..., <var>plot_n</var>], ..., <var>options</var>, ...)</i>
<a name="IDX255"></a>
</dt>
<dt><u>Function:</u> <b>plot2d</b><i> ([<var>plot_1</var>, ..., <var>plot_n</var>], <var>x_range</var>,..., <var>options</var>, ...)</i>
<a name="IDX256"></a>
</dt>
<dd><p>Where <var>plot</var>, <var>plot_1</var>, ..., <var>plot_n</var> can be either
expressions, function names or a list with
the any of the forms: <code>[discrete, [<var>x1</var>, ..., <var>xn</var>],
[<var>y1</var>, ..., <var>yn</var>]]</code>, <code>[discrete, [[<var>x1</var>, <var>y1</var>],
..., [<var>xn</var>, ..., <var>yn</var>]]</code> or <code>[parametric, <var>x_expr</var>,
<var>y_expr</var>, <var>t_range</var>]</code>.
</p>
<p>Displays a plot of one or more expressions as a function of one
variable or parameter.
</p>
<p><code>plot2d</code> displays one or several plots in two dimensions. When
expressions or function name are used to define the plots,
they should all depend on only one variable <var>var</var> and the use of
<var>x_range</var> will be mandatory, to provide the name of the variable and
its minimum and maximum values; the syntax for <var>x_range</var> is:
<code>[<var>variable</var>, <var>min</var>, <var>max</var>]</code>.
</p>
<p>A plot can also be defined in the discrete or parametric forms. The
discrete form is used to plot a set of points with given coordinates. A
discrete plot is defined by a list starting with the keyword
<var>discrete</var>, followed by one or two lists of values. If two lists are
given, they must have the same length; the first list will be
interpreted as the x coordinates of the points to be plotted and the
second list as the y coordinates. If only one list is given after the
<var>discrete</var> keyword, each element on the list should also be a list
with two values that correspond to the x and y coordinates of a point.
</p>
<p>A parametric plot is defined by a list starting with the keyword
<var>parametric</var>, followed by two expressions or function names and a
range for the parameter. The range for the parameter must be a list with
the name of the parameter followed by its minimum and maximum values:
<code>[<var>param</var>, <var>min</var>, <var>max</var>]</code>. The plot will show the path
traced out by the point with coordinates given by the two expressions or
functions, as <var>param</var> increases from <var>min</var> to <var>max</var>.
</p>
<p>A range for the vertical axis is an optional argument with the form:
<code>[y, <var>min</var>, <var>max</var>]</code> (the keyword <var>y</var> is always used for
the vertical axis). If that option is used, the plot will show that
exact vertical range, independently of the values reached by the plot.
If the vertical range is not specified, it will be set up according to
the minimum and maximum values of the second coordinate of the plot
points.
</p>
<p>All other options should also be lists, starting with a keyword and
followed by one or more values. See <code>plot_options</code>.
</p>
<p>If there are several plots to be plotted, a legend will be
written to identiy each of the expressions. The labels that should be
used in that legend can be given with the option <var>legend</var>. If that
option is not used, Maxima will create labels from the expressions or
function names.
</p>
<p><strong>Examples:</strong>
</p>
<p>Plot of a common function:
</p><pre class="example">(%i1) plot2d (sin(x), [x, -%pi, %pi])$
</pre>
<p><div class="image"><img src="./figures/plotting2.gif" alt="figures/plotting2"></div>
</p>
<p>If the functions grows too fast, it might be necessary to limit the
values in the vertical axis using the y option:
</p><pre class="example">(%i1) plot2d (sec(x), [x, -2, 2], [y, -20, 20])$
plot2d: some values were clipped.
</pre>
<p><div class="image"><img src="./figures/plotting3.gif" alt="figures/plotting3"></div>
</p>
<p>The aspect of the plot might be different depending on the plotting
program used. For instance, when the plot box is disable, Xmaxima will
plot the axes using arrows:
</p><pre class="example">(%i1) plot2d ( x^2-1, [x, -3, 3], [y, -2, 10], [box, false],
           [plot_format, xmaxima])$
</pre>
<p><div class="image"><img src="./figures/plotting1.gif" alt="figures/plotting1"></div>
</p>

<p>A plot with a logarithmic scale:
</p><pre class="example">(%i1) plot2d (exp(3*s), [s, -2, 2], [logy])$
</pre>
<p><div class="image"><img src="./figures/plotting4.gif" alt="figures/plotting4"></div>
</p>
<p>Plotting functions by name:
</p><pre class="example">(%i1) F(x) := x^2 $
(%i2) :lisp (defun |$g| (x) (m* x x x))
$g
(%i2) H(x) := if x &lt; 0 then x^4 - 1 else 1 - x^5 $
(%i3) plot2d ([F, G, H], [u, -1, 1], [y, -1.5, 1.5])$
</pre>
<p><div class="image"><img src="./figures/plotting5.gif" alt="figures/plotting5"></div>
</p>
<p>A plot of the butterfly curve, defined parametrically:
</p><pre class="example">(%i1) r: (exp(cos(t))-2*cos(4*t)-sin(t/12)^5)$
(%i2) plot2d([parametric, r*sin(t), r*cos(t), [t, -8*%pi, 8*%pi],
         [nticks, 2000]])$
</pre>
<p><div class="image"><img src="./figures/plotting6.gif" alt="figures/plotting6"></div>
</p>
<p>A &quot;circle&quot; with two turns, when plotted with only 7 points:
</p>
<pre class="example">(%i1) plot2d ([parametric, cos(t), sin(t), [t, -2*%pi, 2*%pi],
           [nticks, 8]])$
</pre>
<p><div class="image"><img src="./figures/plotting7.gif" alt="figures/plotting7"></div>
</p>
<p>Plot of a common function together with the parametric representation of
a circle. The size of the plot has been adjusted with the x and y
options, to make the circle look round and not deformed as an ellipse.
These values work well for the Postscript terminal used to produce this
plot; you might have to adjust the values for your screen.
</p>
<pre class="example">(%i1) plot2d([[parametric, cos(t), sin(t) ,[t,0,2*%pi],
       [nticks, 80]], abs(x)], [x,-2,2], [y, -1.5, 1.5])$
plot2d: some values were clipped.
</pre>
<p><div class="image"><img src="./figures/plotting8.gif" alt="figures/plotting8"></div>
</p>
<p>A plot of a discrete set of points, defining x and y coordinates separately:
</p><pre class="example">(%i1) plot2d ( [ discrete, [10, 20, 30, 40, 50],
               [.6, .9, 1.1, 1.3, 1.4]] )$
</pre>
<p><div class="image"><img src="./figures/plotting9.gif" alt="figures/plotting9"></div>
</p>
<p>The same points shown in the previous example, defining each point
separately and without any lines joining the points:
</p><pre class="example">(%i1) plot2d([discrete, [[10, .6], [20, .9], [30, 1.1], [40, 1.3],
                   [50, 1.4]]], [style, points])$
</pre>
<p><div class="image"><img src="./figures/plotting10.gif" alt="figures/plotting10"></div>
</p>
<p>In this example, a table with three columns is saved in a file
&quot;data.txt&quot; which is then read and the second and third column are
plotted on the two axes:
</p><pre class="example">(%i1) with_stdout (&quot;data.txt&quot;,
         for x:0 thru 10 do print (x, x^2, x^3))$
(%i2) data: transpose ( read_matrix (&quot;data.txt&quot;))$
(%i3) plot2d ([discrete, data[2], data[3]],
        [style,points], [point_type,diamond], [color,red])$
</pre>
<p><div class="image"><img src="./figures/plotting11.gif" alt="figures/plotting11"></div>
</p>
<p>A plot of experimental data points together with the theoretical
function that predicts the data:
</p><pre class="example">(%i1) xy: [[10, .6], [20, .9], [30, 1.1], [40, 1.3], [50, 1.4]]$
(%i2) plot2d([[discrete, xy], 2*%pi*sqrt(l/980)], [l,0,50],
   [style, points, lines], [color, red, blue],
   [point_type, asterisk], [legend, &quot;experiment&quot;, &quot;theory&quot;],
   [xlabel, &quot;pendulum's length (cm)&quot;], [ylabel, &quot;period (s)&quot;])$
</pre>
<p><div class="image"><img src="./figures/plotting12.gif" alt="figures/plotting12"></div>
</p>
<p>See also the section about Plotting Options.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-plot3d"></a>
</p><dl>
<dt><u>Function:</u> <b>plot3d</b><i> (<var>expr</var>, <var>x_range</var>, <var>y_range</var>, ..., <var>options</var>, ...)</i>
<a name="IDX257"></a>
</dt>
<dt><u>Function:</u> <b>plot3d</b><i> ([<var>expr_1</var>, ..., <var>expr_n</var>], <var>x_range</var>, <var>y_range</var>, ..., <var>options</var>, ...)</i>
<a name="IDX258"></a>
</dt>
<dd><p>Displays a plot of one or more surfaces defined as functions of two
variables or in parametric form.
</p>
<p>The functions to be plotted may be specified as expressions or function
names. 
The mouse can be used to rotate the plot looking at the surface
from different sides.
</p>
<p><strong>Examples:</strong>
</p>
<p>Plot of a common function:
</p><pre class="example">(%i1) plot3d (2^(-u^2 + v^2), [u, -3, 3], [v, -2, 2])$
</pre>
<p><div class="image"><img src="./figures/plotting13.gif" alt="figures/plotting13"></div>
</p>
<p>Use of the z option to limit a function that goes to infinity (in this
case the function is minus infinity on the x and y axes); this also
shows how to plot with only lines and no shading:
</p><pre class="example">(%i1) plot3d ( log ( x^2*y^2 ), [x, -2, 2], [y, -2, 2], [z, -8, 4],
         [palette, false], [color, magenta, blue])$
</pre>
<p><div class="image"><img src="./figures/plotting14.gif" alt="figures/plotting14"></div>
</p>
<p>The infinite values of z can also be avoided by choosing a grid that
does not fall on any asymptotes; this example also shows how to select
one of the predefined palettes, in this case the fourth one:
</p><pre class="example">(%i1) plot3d(log(x^2*y^2), [x, -2, 2], [y, -2, 2], [grid, 29, 29],
      [palette, get_plot_option(palette,5)])$
</pre>
<p><div class="image"><img src="./figures/plotting15.gif" alt="figures/plotting15"></div>
</p>
<p>Two surfaces in the same plot, sharing the same domain; in gnuplot the
two surfaces will use the same palette:
</p><pre class="example">(%i1) plot3d ( [2^(-x^2 + y^2), 4*sin(3*(x^2+y^2))/(x^2+y^2),
         [x, -3, 3], [y, -2, 2]])$
</pre>
<p><div class="image"><img src="./figures/plotting16.gif" alt="figures/plotting16"></div>
</p>
<p>The same two surfaces, but now with different domains; in xmaxima each
surface will use a different palette, chosen from the list defined by
the option palette:
</p><pre class="example">(%i1) plot3d ( [[2^(-x^2 + y^2),[x,-2,2],[y,-2,2]],
         4*sin(3*(x^2+y^2))/(x^2+y^2), [x, -3, 3], [y, -2, 2]],
         [plot_format,xmaxima])$
</pre>
<p><div class="image"><img src="./figures/plotting17.gif" alt="figures/plotting17"></div>
</p>
<p>Plot of a Klein bottle, defined parametrically:
</p><pre class="example">(%i1) e_1: 5*cos(x)*(cos(x/2)*cos(y)+sin(x/2)*sin(2*y)+3.0)-10.0$
(%i2) e_2: -5*sin(x)*(cos(x/2)*cos(y)+sin(x/2)*sin(2*y)+3.0)$
(%i3) e_3: 5*(-sin(x/2)*cos(y)+cos(x/2)*sin(2*y))$
(%i4) plot3d ([e_1, e_2, e_3], [x, -%pi, %pi],
        [y, -%pi, %pi], [grid, 40, 40])$
</pre>
<p><div class="image"><img src="./figures/plotting18.gif" alt="figures/plotting18"></div>
</p>
<p>Plot of a spherical harmonic, using of the predefined transformations,
<code>spherical_to_xyz</code>, to transform from spherical to rectangular
coordinates. See the documentation for <code>spherical_to_xyz</code>.
</p><pre class="example">(%i1) plot3d (sin(2*theta)*cos(phi), [theta,0,%pi], [phi,0,2*%pi],
        [transform_xy, spherical_to_xyz], [grid,30,60])$
</pre>
<p><div class="image"><img src="./figures/plotting19.gif" alt="figures/plotting19"></div>
</p>
<p>Use of the predefined function <code>polar_to_xy</code> to transform from
cylindrical to rectangular coordinates. See the documentation for
<code>polar_to_xy</code>. This example also shows how to eliminate the
bounding box and the legend.
</p><pre class="example">(%i1) plot3d(r^.33*cos(th/3), [r,0,1], [th,0,6*%pi], [grid,12,80],
       [transform_xy, polar_to_xy], [box, false], [legend,false])$
</pre>
<p><div class="image"><img src="./figures/plotting20.gif" alt="figures/plotting20"></div>
</p>
<p>Plot of a sphere using the transformation from spherical to rectangular
coordinates. In xmaxima the three axes are scaled in the same
proportion, maintaining the symmetric shape of the sphere. A palette with
different shades of a single color is used:
</p><pre class="example">(%i1) plot3d (5, [theta, 0, %pi], [phi, 0, 2*%pi],
 [transform_xy, spherical_to_xyz], [plot_format,xmaxima],
 [palette,[value,0.65,0.7,0.1,0.9]])$
</pre>
<p><div class="image"><img src="./figures/plotting21.gif" alt="figures/plotting21"></div>
</p>
<p>Definition of a function of two-variables using a matrix. Notice the
single quote in the definition of the function, to prevent plot3d from
failing when it realizes that the matrix will require integer indices.
</p><pre class="example">(%i1) M: matrix([1,2,3,4], [1,2,3,2], [1,2,3,4], [1,2,3,3])$
(%i2) f(x, y) := float('M [round(x), round(y)])$
(%i3) plot3d (f(x,y), [x, 1, 4], [y, 1, 4], [grid, 4, 4])$
apply: subscript must be an integer; found: round(x)
</pre>
<p><div class="image"><img src="./figures/plotting22.gif" alt="figures/plotting22"></div>
</p>
<p>By setting the elevation equal to zero, a surface can be seen as a map
in which each color represents a different level. The option
<code>colorbox</code> is used to show the correspondence among colors and
levels, and the mesh lines are disabled to make the colors easier to see.
</p><pre class="example">(%i1) plot3d (cos (-x^2 + y^3/4), [x, -4, 4], [y, -4, 4],
        [mesh_lines_color, false], [elevation, 0], [azimuth, 0],
        [colorbox, true], [grid, 150, 150])$
</pre>
<p><div class="image"><img src="./figures/plotting23.gif" alt="figures/plotting23"></div>
</p>
<p>See also the section about Plotting Options.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-plot_005foptions"></a>
</p><dl>
<dt><u>System variable:</u> <b>plot_options</b>
<a name="IDX259"></a>
</dt>
<dd><p>Elements of this list state the default options for plotting.
If an option is present in a <code>plot2d</code> or <code>plot3d</code> call,
that value takes precedence over the default option.
Otherwise, the value in <code>plot_options</code> is used.
Default options are assigned by <code>set_plot_option</code>. There are other
local options specific to each plotting command, and not included in
this list of global options.
</p>
<p>Each element of <code>plot_options</code> is a list of two or more items.  The
first item is the name of the option, and the remainder comprises the
value or values assigned to the option.  In some cases, the assigned
value is a list, which may include several items.
</p>
<p>See also <code>set_plot_option</code>, <code>get_option</code> and the section on
Plotting Options.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-set_005fplot_005foption"></a>
</p><dl>
<dt><u>Function:</u> <b>set_plot_option</b><i> (<var>option</var>)</i>
<a name="IDX260"></a>
</dt>
<dd><p>Accepts most of the options listed in the section Plotting Options, and
saves them into the global variable <code>plot_options</code>.
</p>
<p><code>set_plot_option</code> evaluates its argument and returns the complete
list <code>plot_options</code> (after modifying the option given).
</p>
<p>See also <code>plot_options</code>, <code>get_option</code> and the section on
Plotting Options.
</p>
<p>Example:
</p>
<p>Modification of the <code>grid</code> values.
</p>
<pre class="example">(%i1) set_plot_option ([grid, 30, 40]);
(%o1) [[t, - 3, 3], [grid, 30, 40], [transform_xy, false], 
[run_viewer, true], [axes, true], [plot_format, gnuplot_pipes], 
[color, blue, red, green, magenta, black, cyan], 
[point_type, bullet, circle, plus, times, asterisk, box, square, 
triangle, delta, wedge, nabla, diamond, lozenge], 
[palette, [hue, 0.25, 0.7, 0.8, 0.5], 
[hue, 0.65, 0.8, 0.9, 0.55], [hue, 0.55, 0.8, 0.9, 0.4], 
[hue, 0.95, 0.7, 0.8, 0.5]], [gnuplot_term, default], 
[gnuplot_out_file, false], [nticks, 29], [adapt_depth, 5], 
[gnuplot_preamble, ], [gnuplot_default_term_command, 
set term pop], [gnuplot_dumb_term_command, set term dumb 79 22], 
[gnuplot_ps_term_command, set size 1.5, 1.5;set term postscript \
eps enhanced color solid 24], [plot_realpart, false]]
</pre>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-spherical_005fto_005fxyz"></a>
</p><dl>
<dt><u>System function:</u> <b>spherical_to_xyz</b>
<a name="IDX261"></a>
</dt>
<dd><p>It can be given as value for the <code>transform_xy</code> option of
plot3d. Its effect will be to interpret the two independent variables
and the function in plot3d as the spherical coordinates of a point
(first, the angle with the z axis, then the angle of the xy projection
with the x axis and finally the distance from the origin) and transform
them into x, y and z coordinates.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-Plotting-Options"></a>
</p><hr size="6">
<a name="Plotting-Options"></a>
<a name="SEC35"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC34" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC36" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.4 Plotting Options </h2>

<p>All options consist of a list starting with one of the keywords in this
section, followed by one or more values. Most of the options can be used
in any of the plotting commands (<var>plot2d</var>, <var>plot3d</var>, <var>contour_plot</var>,
<var>implicit_plot</var>) or in the function <var>set_plot_option</var>; the
exceptions will be specified in the following list.
</p>
<p><a name="Item_003a-adapth_005fdepth"></a>
</p><dl>
<dt><u>Plot option:</u> <b>adapth_depth</b><i> [adapth_depth, <var>integer</var>]</i>
<a name="IDX262"></a>
</dt>
<dd><p>The maximum number of splittings used by the adaptive plotting routine.
</p>
<p>Default value: 5
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-axes"></a>
</p><dl>
<dt><u>Plot option:</u> <b>axes</b><i> [axes, <var>symbol</var>] </i>
<a name="IDX263"></a>
</dt>
<dd><p>Where <var>symbol</var> can be either <code>true</code>, <code>false</code>, <code>x</code> or
<code>y</code>.  If <code>false</code>, no axes will be shown; if equal to <code>x</code>
or <code>y</code> only the x or y axis will be shown, and if it is equal to
<code>true</code>, both axes will be shown. This option is used only by plot2d
and implicit_plot.
</p>
<p>Default value: true
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-azimut"></a>
</p><dl>
<dt><u>Plot option:</u> <b>azimut</b><i> [azimuth, <var>number</var>]</i>
<a name="IDX264"></a>
</dt>
<dd><p>A plot3d plot can be thought of as starting with its x and y axis
in the horizontal and vertical axis, as in plot2d, and the z axis
coming out of the paper perpendicularly. The z axis is then rotated
around the x axis an angle equals to <code>elevation</code> and then the xy
plane is rotated around the new z axis an angle <code>azimuth</code>. This
option sets the value for the azimuth, in degrees.
</p>
<p>Default value: 30
</p>
<p>See also  <code>elevation</code>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>


<dl>
<dt><u>Plot option:</u> <b>box</b><i> [box, <var>symbol</var>]</i>
<a name="IDX265"></a>
</dt>
<dd><p>If set to <code>true</code>, a bounding box will be drawn for the plot; if set
to <code>false</code>, no box will be drawn.
</p>
<p>Default value: <code>true</code>
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-color"></a>
</p><dl>
<dt><u>Plot option:</u> <b>color</b><i> [color, <var>color_1</var>, ..., <var>color_n</var>]</i>
<a name="IDX266"></a>
</dt>
<dd><p>In plot2d and implicit_plot, it defines the color (or colors) for the
various curves. In plot3d, it defines the colors used for the mesh lines
of the surfaces, when no palette is being used; one side of the surface
will have color <var>color_1</var> and the other <var>color_2</var> (or the same
color if there is only one color).
</p>
<p>If there are more curves or surfaces than colors, the colors will be repeated in
sequence. When using gnuplot, the colors could be: blue, red, green,
magenta, black, cyan or black; in xmaxima the colors can be those or a
string starting with the character # and followed by six hexadecimal
digits: two for the red component, two for green component and two for
the blue component. If given the name of an unknown color, black will be
used instead.
</p> 
<p>Default value: blue, red, green, magenta, black, cyan
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-colorbox"></a>
</p><dl>
<dt><u>Plot option:</u> <b>colorbox</b><i> [colorbox, <var>symbol</var>]</i>
<a name="IDX267"></a>
</dt>
<dd><p>Where <var>symbol</var> can be either <code>true</code> or <code>false</code>. If
<code>true</code>, whenever plot3d uses a palette of different colors to
represent the different values of z, a box will be shown on the right,
indicating the colors used according to the scale of values of z. This
option does not work in xmaxima.
</p>
<p>Default value: <code>false</code>
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-elevation"></a>
</p><dl>
<dt><u>Plot option:</u> <b>elevation</b><i> [elevation, <var>number</var>]</i>
<a name="IDX268"></a>
</dt>
<dd><p>A plot3d plot can be thought of as starting with its x and y axis
in the horizontal and vertical axis, as in plot2d, and the z axis
coming out of the paper perpendicularly. The z axis is then rotated
around the x axis an angle equals to <code>elevation</code> and then the xy
plane is rotated around the new z axis an angle <code>azimuth</code>. This
option sets the value for the elevation, in degrees.
</p>
<p>Default value: 60
</p>
<p>See also  <code>azimuth</code>.
</p>

<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-grid"></a>
</p><dl>
<dt><u>Plot option:</u> <b>grid</b><i> [grid, <var>integer</var>, <var>integer</var>]</i>
<a name="IDX269"></a>
</dt>
<dd><p>Sets the number of grid points to use in the x- and y-directions
for three-dimensional plotting.
</p>
<p>Default value: 30, 30
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-legend"></a>
</p><dl>
<dt><u>Plot option:</u> <b>legend</b><i> [legend, <var>string_1</var>, ..., <var>string_n</var>]</i>
<a name="IDX270"></a>
</dt>
<dt><u>Plot option:</u> <b>legend</b><i> [legend, <var>false</var>]</i>
<a name="IDX271"></a>
</dt>
<dd><p>It specifies the labels for the plots when various plots are shown. If
there are more plots than the number of labels given, they will be
repeated. If given the value <code>false</code>, no legends will be shown. By
default, the names of the expressions or functions will be used, or the
words discrete1, discrete2, ..., for discrete sets of points. This
option can not be set with <var>set_plot_option</var>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-logx"></a>
</p><dl>
<dt><u>Plot option:</u> <b>logx</b><i> [logx]</i>
<a name="IDX272"></a>
</dt>
<dd><p>Makes the horizontal axes to be scaled logarithmically. It can not be
used with <var>set_plot_option</var>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-logy"></a>
</p><dl>
<dt><u>Plot option:</u> <b>logy</b><i> [logy]</i>
<a name="IDX273"></a>
</dt>
<dd><p>Makes the vertical axes to be scaled logarithmically. It can not be used
with <var>set_plot_option</var>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-mesh_005flines_005fcolor"></a>
</p><dl>
<dt><u>Plot option:</u> <b>mesh_lines_color</b><i> [mesh_lines_color, <var>color</var>]</i>
<a name="IDX274"></a>
</dt>
<dd><p>It sets the color used by plot3d to draw the mesh lines, when a palette is
being used. It accepts the same colors as for the option <code>color</code>
(see the list of allowed colors in <code>color</code>). It can also be given a
value <code>false</code> to eliminate completely the mesh lines.
</p>
<p>Default value: black
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-nticks"></a>
</p><dl>
<dt><u>Plot option:</u> <b>nticks</b><i> [nticks, <var>integer</var>]</i>
<a name="IDX275"></a>
</dt>
<dd><p>When plotting functions with plot2d, it is gives the initial number of
points used by the adaptive plotting routine for plotting
functions. When plotting parametric functions with plot2d or plot3d,
it sets the number of points that will be shown for the plot.
</p>
<p>Default value: 29
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-palette"></a>
</p><dl>
<dt><u>Plot option:</u> <b>palette</b><i> [palette, [<var>palette_1</var>], ..., [<var>palette_n</var>]]</i>
<a name="IDX276"></a>
</dt>
<dt><u>Plot option:</u> <b>palette</b><i> [palette, <var>false</var>]</i>
<a name="IDX277"></a>
</dt>
<dd><p>It can consist of one palette or a list of several palettes. Each
palette is a list with a keyword followed by four numbers. The first
three numbers, which must be between 0 and 1, define the hue, saturation
and value of a basic color to be assigned to the minimum value of z. The
keyword specifies which of the three attributes (hue, saturation or
value) will be increased according to the values of z. The last number
indicates the increase corresponding to the maximum value of z. That
last number can be bigger than 1 or negative; the corresponding values
of the modified attribute will be rounded modulo 1.
</p>
<p>Gnuplot only uses the first palette in the list; xmaxima will use the
palettes in the list sequentially, when several surfaces are plotted
together; if the number of palettes is exhausted, they will be repeated
sequentially.
</p>
<p>The color of the mesh lines will be given by the option
<code>mesh_lines_color</code>.  If <code>palette</code> is given the value
<code>false</code>, the surfaces will not be shaded but represented with a
mesh of curves only. In that case, the colors of the lines will be
determined by the option <code>color</code>.
</p>
<p>Default value: [hue, 0.25, 0.7, 0.8, 0.5], [hue, 0.65, 0.8, 0.9, 0.55], [hue, 0.55, 0.8, 0.9, 0.4], [hue, 0.95, 0.7, 0.8, 0.5]
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-plot_005fformat"></a>
</p><dl>
<dt><u>Plot option:</u> <b>plot_format</b><i> [plot_format, <var>format</var>]</i>
<a name="IDX278"></a>
</dt>
<dd><p>Where <var>format</var> is one of the following: gnuplot, xmaxima, mgnuplot or
gnuplot_pipes.
</p>
<p>It sets the format to be used for plotting.
</p>
<p>Default value: gnuplot, in Windows systems, or gnuplot_pipes in other systems.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-plot_005freal_005fpart"></a>
</p><dl>
<dt><u>Plot option:</u> <b>plot_real_part</b><i> [plot_realpart, <var>symbol</var>]</i>
<a name="IDX279"></a>
</dt>
<dd><p>When set to <code>true</code>, the functions to be plotted will be considered
as complex functions whose real value should be plotted; this is
equivalent to plotting <code>realpart(<var>function</var>)</code>. I set to
<code>false</code>, nothing will be plotted when the function does not give a
real value. For instance, when <code>x</code> is negative, <code>log(x)</code> gives
a complex value, with real value equal to <code>log(abs(x))</code>; if
<code>plot_real_part</code> were <code>true</code>, <code>log(-5)</code> would be plotted
as <code>log(5)</code>, while nothing would be plotted if
<code>plot_real_part</code> were <code>false</code>.
</p>
<p>Default value: <code>false</code>
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-point_005ftype"></a>
</p><dl>
<dt><u>Plot option:</u> <b>point_type</b><i> [point_type, <var>type_1</var>, ..., <var>type_n</var>]</i>
<a name="IDX280"></a>
</dt>
<dd><p>In gnuplot, each set of points to be plotted with the style &quot;points&quot;
or &quot;linespoints&quot; will be represented with objects taken from this
list, in sequential order. If there are more sets of points than objects
in this list, they will be repeated sequentially.
The possible objects that can be used are: bullet, circle, plus, times,
asterisk, box, square,triangle, delta, wedge, nabla, diamond or lozenge
</p>
<p>Default value: bullet, circle, plus, times, asterisk, box, square,triangle, delta, wedge, nabla, diamond, lozenge
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-psfile"></a>
</p><dl>
<dt><u>Plot option:</u> <b>psfile</b><i> [psfile, <var>string</var>]</i>
<a name="IDX281"></a>
</dt>
<dd><p>Saves the plot into a Postscript file with name equal to <var>string</var>,
rather than showing it in the screen. By default, the file will be
created in the directory defined by the variable <var>maxima_tempdir</var>;
the value of that variable can be changed to save the file in a
different directory.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-run_005fviewer"></a>
</p><dl>
<dt><u>Plot option:</u> <b>run_viewer</b><i> [run_viewer, <var>symbol</var>]</i>
<a name="IDX282"></a>
</dt>
<dd><p>Controls whether or not the appropriate viewer for the plot format
should be run.
</p>
<p>Default value: <code>true</code>
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-style"></a>
</p><dl>
<dt><u>Plot option:</u> <b>style</b><i> [style, <var>type_1</var>, ..., <var>type1_n</var>]</i>
<a name="IDX283"></a>
</dt>
<dt><u>Plot option:</u> <b>style</b><i> [style, [<var>style_1</var>], ..., [<var>style_n</var>]]</i>
<a name="IDX284"></a>
</dt>
<dd><p>The styles that will be used for the various functions or sets of data
in a 2d plot. The word <var>style</var> must be followed by one or more
styles. If there are more functions and data sets than the styles
given, the styles will be repeated. Each style can be either
<var>lines</var> for line segments, <var>points</var> for isolated points,
<var>linespoints</var> for segments and points, or <var>dots</var> for small
isolated dots. Gnuplot accepts also an <var>impulses</var> style.
</p>
<p>Each of the styles can be enclosed inside a list with some aditional
parameters. <var>lines</var> accepts one or two numbers: the width of the
line and an integer that identifies a color. The default color codes
are: 1: blue, 2: red, 3: magenta, 4: orange, 5: brown, 6: lime and 7:
aqua. If you use Gnuplot with a terminal different than X11,
those colors might be different; for example, if you use the option
[<var>gnuplot_term</var>,<var>ps</var>], color index 4 will correspond to black,
instead of orange.
</p>
<p><var>points</var> accepts one two or three parameters; the first parameter
is the radius of the points, the second parameter is an integer that
selects the color, using the same code used for <var>lines</var> and the
third parameter is currently used only by Gnuplot and it corresponds
to several objects instead of points. The default types of
objects are: 1: filled circles, 2: open circles, 3: plus signs, 4: x,
5: *, 6: filled squares, 7: open squares, 8: filled triangles, 9: open
triangles, 10: filled inverted triangles, 11: open inverted triangles,
12: filled lozenges and 13: open lozenges.
</p>
<p><var>linesdots</var> accepts up to four parameters: line width, points
radius, color and type of object to replace the points.
</p>
<p>Default value: <var>lines</var> (will plot all sets of points joined with
lines of thickness 1 and the first color given by the option <code>color</code>).
</p>
<p>See also <code>color</code> and <code>point_type</code>.
</p> 
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>


<p><a name="Item_003a-t"></a>
</p><dl>
<dt><u>Plot option:</u> <b>t</b><i> [t, <var>min</var>, <var>max</var>]</i>
<a name="IDX285"></a>
</dt>
<dd><p>Default range for parametric plots.
</p>
<p>Default value: -3, 3
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-transform_005fxy"></a>
</p><dl>
<dt><u>Plot option:</u> <b>transform_xy</b><i> [transform_xy, <var>symbol</var>]</i>
<a name="IDX286"></a>
</dt>
<dd><p>Where <var>symbol</var> is either <code>false</code> or the result obtained by
using the function <code>transform_xy</code>. If different from <code>false</code>,
it will be used to transform the 3 coordinates in plot3d.
</p>
<p>Default value: <code>false</code>
</p>
<p>See <code>make_transform</code>, <code>polar_to_xy</code> and
<code>spherical_to_xyz</code>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-x"></a>
</p><dl>
<dt><u>Plot option:</u> <b>x</b><i> [x, <var>min</var>, <var>max</var>]</i>
<a name="IDX287"></a>
</dt>
<dd><p>When used as the first option in a 2d-plotting command (or any of the
first two in plot3d), it indicates that the first independent variable
is x and it sets its range. It can also be used again after the first
option (or after the second option in plot3d) to define the effective
horizontal domain that will be shown in the plot.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-xlabel"></a>
</p><dl>
<dt><u>Plot option:</u> <b>xlabel</b><i> [xlabel, <var>string</var>]</i>
<a name="IDX288"></a>
</dt>
<dd><p>Specifies the <var>string</var> that will label the first axis; if this
option is not used, that label will be the name of the independent
variable, when plotting functions with plot2d or implicit_plot, or the
name of the first variable, when plotting surfaces with plot3d or
contours with contour_plot, or the first expression in the case of a
parametric plot. It can not be used with <var>set_plot_option</var>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-y"></a>
</p><dl>
<dt><u>Plot option:</u> <b>y</b><i> [y, <var>min</var>, <var>max</var>]</i>
<a name="IDX289"></a>
</dt>
<dd><p>When used as one of the first two options in plot3d, it indicates that
one of the independent variables is y and it sets its range. Otherwise,
It defines the effective domain of the second variable that will be
shown in the plot.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-ylabel"></a>
</p><dl>
<dt><u>Plot option:</u> <b>ylabel</b><i> [ylabel, <var>string</var>]</i>
<a name="IDX290"></a>
</dt>
<dd><p>Specifies the <var>string</var> that will label the second axis; if this
option is not used, that label will be &quot;y&quot;, when plotting functions
with plot2d or implicit_plot, or the name of the second variable, when
plotting surfaces with plot3d or contours with contour_plot, or the
second expression in the case of a parametric plot. It can not be used
with <var>set_plot_option</var>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-z"></a>
</p><dl>
<dt><u>Plot option:</u> <b>z</b><i> [z, <var>min</var>, <var>max</var>]</i>
<a name="IDX291"></a>
</dt>
<dd><p>Used in plot3d to set the effective range of values of z that will be
shown in the plot.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-zlabel"></a>
</p><dl>
<dt><u>Plot option:</u> <b>zlabel</b><i> [zlabel, <var>string</var>]</i>
<a name="IDX292"></a>
</dt>
<dd><p>Specifies the <var>string</var> that will label the third axis, when using
plot3d. If this option is not used, that label will be &quot;z&quot;, when
plotting surfaces, or the third expression in the case of a parametric
plot. It can not be used with <var>set_plot_option</var> and it will be
ignored by plot2d and implicit_plot.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-Gnuplot-Options"></a>
</p><hr size="6">
<a name="Gnuplot-Options"></a>
<a name="SEC36"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC35" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC37" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.5 Gnuplot Options </h2>

<p>There are several plot options specific to gnuplot. All of them consist
of a keyword (the name of the option), followed by a string that should
be a valid gnuplot command, to be passed directly to gnuplot. In most
cases, there exist a corresponding plotting option that will produce a
similar result and whose use is more recommended than the gnuplot
specific option.
</p>
<p><a name="Item_003a-gnuplot_005fterm"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_term</b>
<a name="IDX293"></a>
</dt>
<dd><p>Sets the output terminal type for gnuplot.
</p><ul>
<li>
<strong>default</strong> (default value)

<p>Gnuplot output is displayed in a separate graphical window.
</p>
</li><li>
<strong>dumb</strong>

<p>Gnuplot output is displayed in the Maxima console by an &quot;ASCII art&quot; approximation to graphics.
</p>
</li><li>
<strong>ps</strong>

<p>Gnuplot generates commands in the PostScript page description language.
If the option <code>gnuplot_out_file</code> is set to <var>filename</var>, gnuplot
writes the PostScript commands to <var>filename</var>.  Otherwise, it is
saved as <code>maxplot.ps</code> file.
</p>
</li><li>
any other valid gnuplot term specification

<p>Gnuplot can generate output in many other graphical formats such
as png, jpeg, svg etc.  To create plot in all these formats the
<code>gnuplot_term</code> can be set to any supported gnuplot term name (symbol) 
or even full gnuplot term specification with any valid options (string).
For example <code>[gnuplot_term,png]</code> creates output in PNG (Portable
Network Graphics) format while <code>[gnuplot_term,&quot;png size 1000,1000&quot;]</code>
creates PNG of 1000x1000 pixels size. 
If the option <code>gnuplot_out_file</code> is set to <var>filename</var>, gnuplot 
writes the output to <var>filename</var>. Otherwise, it is saved as 
<code>maxplot.<var>term</var></code> file, where <var>term</var> is gnuplot 
terminal name.
</p></li></ul>

<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fout_005ffile"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_out_file</b>
<a name="IDX294"></a>
</dt>
<dd><p>When used in conjunction with the <code>gnuplot_term</code> option, it can be
used to save the plot in a file, in one of the graphic formats supported
by Gnuplot. If you want to create a Postscript file, you can use the
option <code>psfile</code> instead, which will also work in Openmath, and does
the same thing with just one option.
</p>
<pre class="example">[gnuplot_term, png], [gnuplot_out_file, &quot;graph3.png&quot;]
</pre>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fpm3d"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_pm3d</b>
<a name="IDX295"></a>
</dt>
<dd><p>With a value of <code>false</code>, it can be used to prevent the usage of
PM3D mode, which is enabled by default.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fpreamble"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_preamble</b>
<a name="IDX296"></a>
</dt>
<dd><p>Inserts gnuplot commands before the plot is drawn. Any valid gnuplot
commands may be used. Multiple commands should be separated with a
semi-colon. The example shown produces a log scale plot. The default
value for <code>gnuplot_preamble</code> is the empty string <code>&quot;&quot;</code>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fcurve_005ftitles"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_curve_titles</b>
<a name="IDX297"></a>
</dt>
<dd><p>This is an old option that has been replaced by <em>legend</em> described
above.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fcurve_005fstyles"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_curve_styles</b>
<a name="IDX298"></a>
</dt>
<dd><p>This is an obsolete option that has been replaced by <em>style</em>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fdefault_005fterm_005fcommand"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_default_term_command</b>
<a name="IDX299"></a>
</dt>
<dd><p>The gnuplot command to set the terminal type for the default
terminal. The default value is <code>set term pop</code>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fdumb_005fterm_005fcommand"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_dumb_term_command</b>
<a name="IDX300"></a>
</dt>
<dd><p>The gnuplot command to set the terminal type for the dumb terminal. The
default value is <code>&quot;set term dumb 79 22&quot;</code>, which makes the text
output 79 characters by 22 characters.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fps_005fterm_005fcommand"></a>
</p><dl>
<dt><u>Plot option:</u> <b>gnuplot_ps_term_command</b>
<a name="IDX301"></a>
</dt>
<dd><p>The gnuplot command to set the terminal type for the PostScript
terminal. The default value is <code>&quot;set size 1.5, 1.5;set term
postscript eps enhanced color solid 24&quot;</code>, which sets the size to 1.5
times gnuplot's default, and the font size to 24, among other
things. See the gnuplot documentation for <code>set term postscript</code> for
more information.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-Gnuplot_005fpipes-Format-Functions"></a>
</p><hr size="6">
<a name="Gnuplot_005fpipes-Format-Functions"></a>
<a name="SEC37"></a>
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC36" title="Previous section in reading order"> &lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next section in reading order"> &gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="#SEC31" title="Up section"> Up </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<h2 class="section"> 8.6 Gnuplot_pipes Format Functions </h2>

<p><a name="Item_003a-gnuplot_005fstart"></a>
</p><dl>
<dt><u>Function:</u> <b>gnuplot_start</b><i> ()</i>
<a name="IDX302"></a>
</dt>
<dd><p>Opens the pipe to gnuplot used for plotting with the
<code>gnuplot_pipes</code> format. Is not necessary to manually open the
pipe before plotting.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005fclose"></a>
</p><dl>
<dt><u>Function:</u> <b>gnuplot_close</b><i> ()</i>
<a name="IDX303"></a>
</dt>
<dd><p>Closes the pipe to gnuplot which is used with the <code>gnuplot_pipes</code>
format.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005frestart"></a>
</p><dl>
<dt><u>Function:</u> <b>gnuplot_restart</b><i> ()</i>
<a name="IDX304"></a>
</dt>
<dd><p>Closes the pipe to gnuplot which is used with the <code>gnuplot_pipes</code>
format and opens a new pipe.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005freplot"></a>
</p><dl>
<dt><u>Function:</u> <b>gnuplot_replot</b><i> ()</i>
<a name="IDX305"></a>
</dt>
<dt><u>Function:</u> <b>gnuplot_replot</b><i> (<var>s</var>)</i>
<a name="IDX306"></a>
</dt>
<dd><p>Updates the gnuplot window. If <code>gnuplot_replot</code> is called with a
gnuplot command in a string <var>s</var>, then <code>s</code> is sent to gnuplot
before reploting the window.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>

<p><a name="Item_003a-gnuplot_005freset"></a>
</p><dl>
<dt><u>Function:</u> <b>gnuplot_reset</b><i> ()</i>
<a name="IDX307"></a>
</dt>
<dd><p>Resets the state of gnuplot used with the <code>gnuplot_pipes</code>
format. To update the gnuplot window call <code>gnuplot_replot</code> after
<code>gnuplot_reset</code>.
</p>
<div class=categorybox>


<p>Categories:&nbsp;&nbsp;<a href="maxima_95.html#Category_003a-Plotting">Plotting</a>
</p>
</div>


</dd></dl>


<p><a name="Item_003a-Input-and-Output"></a>
</p><hr size="6">
<table cellpadding="1" cellspacing="1" border="0">
<tr><td valign="middle" align="left">[<a href="#SEC31" title="Beginning of this chapter or previous chapter"> &lt;&lt; </a>]</td>
<td valign="middle" align="left">[<a href="maxima_9.html#SEC38" title="Next chapter"> &gt;&gt; </a>]</td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left"> &nbsp; </td>
<td valign="middle" align="left">[<a href="maxima.html#SEC_Top" title="Cover (top) of document">Top</a>]</td>
<td valign="middle" align="left">[<a href="maxima_toc.html#SEC_Contents" title="Table of contents">Contents</a>]</td>
<td valign="middle" align="left">[<a href="maxima_79.html#SEC331" title="Index">Index</a>]</td>
<td valign="middle" align="left">[<a href="maxima_abt.html#SEC_About" title="About (help)"> ? </a>]</td>
</tr></table>
<p>
 <font size="-1">
  This document was generated by <em>Robert Dodier</em> on <em>April, 24 2010</em> using <a href="http://texi2html.cvshome.org/"><em>texi2html 1.76</em></a>.
 </font>
 <br>

</p>
</body>
</html>