In the discussion a "point" is a datum defined by a single record in the file.
Syntax:
plot 'file' every {<point_incr>} {:{<line_incr>} {:{<start_point>} {:{<start_line>} {:{<end_point>} {:<end_line>}}}}}
The data points to be plotted are selected according to a loop from <start_point> to <end_point> with increment <point_incr> and the datalines according to a loop from <start_line> to <end_line> with increment <line_incr>.
The first datum in each dataline is numbered '0', as is the first dataline in the file.
Note that records containing unplottable information are counted.
Any of the numbers can be omitted; the increments default to unity, the start values to the first point or dataline, and the end values to the last point or dataline. If every is not specified, all points in all datalines are plotted.
Examples:
every :::3::3 # selects just the fourth dataline ('0' is first) every :::::9 # selects the first 10 datalines every 2:2 # selects every other point in every other dataline every ::5::15 # selects points 5 through 15 in each dataline