1
d3.extent = function(array, f) {
7
if (arguments.length === 1) {
8
while (++i < n && ((a = c = array[i]) == null || a != a)) a = c = undefined;
9
while (++i < n) if ((b = array[i]) != null) {
14
while (++i < n && ((a = c = f.call(array, array[i], i)) == null || a != a)) a = undefined;
15
while (++i < n) if ((b = f.call(array, array[i], i)) != null) {