plsdiplz: Set parameters incrementally (zoom mode) that define current plot-space window

Set relative minima and maxima incrementally (zoom mode) that define the current plot-space window. This function has the same effect as plsdiplt if that function has not been previously called. Otherwise, this function implements zoom mode using the transformation min_used = old_min + old_length*min and max_used = old_min + old_length*max for each axis. For example, if min = 0.05 and max = 0.95 for each axis, repeated calls to plsdiplz will zoom in by 10 per cent for each call.

xmin (PLFLT, input) Relative (incremental) minimum in x. ymin (PLFLT, input) Relative (incremental) minimum in y. xmax (PLFLT, input) Relative (incremental) maximum in x. ymax (PLFLT, input) Relative (incremental) maximum in y.