3.25.53 pm3d

pm3d is an ‘splot‘ style for drawing palette-mapped 3d and 4d data as color/gray maps and surfaces. It uses an algorithm that allows plotting gridded as well as non-gridded data without preprocessing, even when the data scans do not have the same number of points.

Syntax (the options can be given in any order):

      set pm3d {
                 { at <position> }
                 { interpolate <steps/points in scan, between scans> }
                 { scansautomatic | scansforward | scansbackward | depthorder }
                 { flush { begin | center | end } }
                 { ftriangles | noftriangles }
                 { clip1in | clip4in }
                 { corners2color { mean|geomean|median|min|max|c1|c2|c3|c4 } }
                 { hidden3d {<linestyle>} | nohidden3d }
                 { implicit | explicit }
                 { map }
               }
      show pm3d
      unset pm3d

A pm3d color surface is drawn if the splot command specifies pm3d, if the data or function style is set to pm3d globally, or if the pm3d mode is ‘set pm3d implicit‘. In the latter two cases, the pm3d surface is draw in addition to the mesh produced by the style specified in the plot command. E.g.

      splot 'fred.dat' with lines, 'lola.dat' with lines

would draw both a mesh of lines and a pm3d surface for each data set. If the option ‘explicit‘ is on (or ‘implicit‘ is off) only plots specified by the pm3d attribute are plotted with a pm3d surface, e.g.:

      splot 'fred.dat' with lines, 'lola.dat' with pm3d

would plot ’fred.dat’ with lines (only) and ’lola.dat’ with a pm3d surface.

On gnuplot start-up, the mode is ‘explicit‘. For historical and compatibility reasons, the commands ‘set pm3d;‘ (i.e. no options) and ‘set pm3d at X ...‘ (i.e. ‘at‘ is the first option) change the mode to ‘implicit‘. The command ‘set pm3d;‘ sets other options to their default state.

If you set the default data or function style to pm3d, e.g.:

      set style data pm3d

then the options ‘implicit‘ and ‘explicit‘ have no effect.

Note that when plotting several plots, they are plotted in the order given on the command line. This can be of interest especially for filled surfaces which can overwrite and therefore hide part of earlier plots.

The pm3d coloring can be drawn at any or all of three different positions, ‘top‘, ‘bottom‘, or surface. See position. The following command draws three color surfaces at different altitudes:

      set border 4095
      set pm3d at s
      splot 10*x with pm3d at b, x*x-y*y, x*x+y*y with pm3d at t

See also help for palette, cbrange, ‘set colorbox‘, and definitely the demo file ‘demo/pm3d.dem‘.

This document was generated on April 4, 2012 using texi2html 5.0.