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SUBROUTINE DLARFB( SIDE, TRANS, DIRECT, STOREV, M, N, K, V, LDV,
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$ T, LDT, C, LDC, WORK, LDWORK )
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* -- LAPACK auxiliary routine (version 3.2) --
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* -- LAPACK is a software package provided by Univ. of Tennessee, --
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* -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..--
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* Modified by R. Clint Whaley for inclusion in ATLAS Dec 2009.
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* .. Scalar Arguments ..
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CHARACTER DIRECT, SIDE, STOREV, TRANS
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INTEGER K, LDC, LDT, LDV, LDWORK, M, N
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* .. Array Arguments ..
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DOUBLE PRECISION C( LDC, * ), T( LDT, * ), V( LDV, * ),
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* DLARFB applies a real block reflector H or its transpose H' to a
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* real m by n matrix C, from either the left or the right.
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* SIDE (input) CHARACTER*1
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* = 'L': apply H or H**T from the Left
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* = 'R': apply H or H**T from the Right
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* TRANS (input) CHARACTER*1
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* = 'N': apply H (No transpose)
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* = 'T': apply H**T (Transpose)
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* DIRECT (input) CHARACTER*1
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* Indicates how H is formed from a product of elementary
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* = 'F': H = H(1) H(2) . . . H(k) (Forward)
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* = 'B': H = H(k) . . . H(2) H(1) (Backward)
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* STOREV (input) CHARACTER*1
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* Indicates how the vectors which define the elementary
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* reflectors are stored:
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* The number of rows of the matrix C.
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* The number of columns of the matrix C.
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* The order of the matrix T (= the number of elementary
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* reflectors whose product defines the block reflector).
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* V (input) DOUBLE PRECISION array, dimension
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* (LDV,K) if STOREV = 'C'
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* (LDV,M) if STOREV = 'R' and SIDE = 'L'
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* (LDV,N) if STOREV = 'R' and SIDE = 'R'
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* The matrix V. See further details.
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* The leading dimension of the array V.
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* If STOREV = 'C' and SIDE = 'L', LDV >= max(1,M);
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* if STOREV = 'C' and SIDE = 'R', LDV >= max(1,N);
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* if STOREV = 'R', LDV >= K.
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* T (input) DOUBLE PRECISION array, dimension (LDT,K)
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* The triangular k by k matrix T in the representation of the
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* The leading dimension of the array T. LDT >= K.
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* C (input/output) DOUBLE PRECISION array, dimension (LDC,N)
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* On entry, the m by n matrix C.
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* On exit, C is overwritten by H*C or H'*C or C*H or C*H'.
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* The leading dimension of the array C. LDC >= max(1,M).
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* WORK (workspace) DOUBLE PRECISION array, dimension (LDWORK,K)
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* LDWORK (input) INTEGER
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* The leading dimension of the array WORK.
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* If SIDE = 'L', LDWORK >= max(1,N);
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* if SIDE = 'R', LDWORK >= max(1,M).
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* =====================================================================
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INTEGER ATLASROWMAJOR, ATLASCOLMAJOR
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PARAMETER (ATLASROWMAJOR=101, ATLASCOLMAJOR=102)
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INTEGER ATLASNOTRANS, ATLASTRANS, ATLASCONJTRANS
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PARAMETER (ATLASNOTRANS=111, ATLASTRANS=112, ATLASCONJTRANS=113)
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INTEGER ATLASUPPER, ATLASLOWER
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PARAMETER (ATLASUPPER=121, ATLASLOWER=122)
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INTEGER ATLASNONUNIT, ATLASUNIT
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PARAMETER (ATLASNONUNIT=131, ATLASUNIT=132)
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INTEGER ATLASLEFT, ATLASRIGHT
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PARAMETER (ATLASLEFT=141, ATLASRIGHT=142)
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* .. Local variables ..
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INTEGER ISIDE, ITRANS, IDIRECT, ISTORE
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* .. Executable Statements ..
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* Quick return if possible
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IF( M.LE.0 .OR. N.LE.0 )
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IF (SIDE.EQ.'R' .OR. SIDE.EQ.'r') THEN
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IF (TRANS.EQ.'N' .OR. TRANS.EQ.'n') THEN
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ITRANS = ATLASNOTRANS
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IF (DIRECT.EQ.'F' .OR. DIRECT.EQ.'f') THEN
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IF (STOREV.EQ.'R' .OR. STOREV.EQ.'r') THEN
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CALL ATL_F77WRAP_DLARFB(ISIDE, ITRANS, IDIRECT, ISTORE, M, N, K,
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$ V, LDV, T, LDT, C, LDC, WORK, LDWORK)
added
removed
interfaces/lapack/F77/src/dlarfb.f
