The sampling rate of functions may be changed by the set samples command. By default, sampling is set to 100 points. A higher sampling rate will produce more accurate plots, but will take longer. This parameter no longer has any effect on data-file plotting.
Syntax:
set samples <samples_1> {,<samples_2>}
show samples
When a 2-d plot is being done, only the value of <samples_1> is relevant.
When a surface plot is being done without the removal of hidden
lines, the value of samples specifies the number of samples that are
evaluated per iso line. Each iso-v line will have <sample_1> samples
and each iso-u line will have <sample_2> samples. If you only specify
<samples_1>, <samples_2> will be set to the same value as <samples_1>.
See also set isosamples.