[Gnuplot-info] Problems with pm3d

[Joe K. <jko...@co...>]

As the graphics part of octave, I have used gnuplot indirectly for over a
year, but now I'm having some problems with my first "standalone" gnuplot
attempt. I'm using gnuplot 4.0 patchlevel 0 on a Mac G5 with the AquaTerm
interface under OS X 10.3.5. All the .dem files seem to be performing
correctly.

With an existing Fortran application, I least-squares fit a polynomial
surface to some data points and wrote the results as an 81 x 81 grid to an
ASCII file with 6561 lines of x,y,z triplets in E format. When I do a basic
splot of the data, the surface correctly appears with the correct data
ranges.

When I attempt to represent the data with pm3d, I have a problem. Here is
what I tried:

gnuplot> set palette color
gnuplot> set pm3d map
gnuplot> splot 'test5020_5.fpt' with pm3d

Where 'test5020_5.fpt' is the ASCII file with the data in x,y,z triplets. At
this point I get a blank frame (all white inside the boundary) with the
correct frame dimensions (0.0 < x < 1.0, 0.0 < y < 1.0), and a colorbar to
the right in the correct range of 260 to 380.  I have tried gnuplot input
files with scanning left-to-right, bottom-to-top and vice versa with the
same results.

How do I get gnuplot to color the inside of the frame consistent with the
colorbar colors? What am I missing? Thanks for any help.

Joe