[Gnuplot-bugs] [gnuplot-bug] contour line styles and colors

[Ekrenor <ek...@gm...>]

Dear all,

I am puzzled by a strange behaviour when trying to set the line styles
and colors in the contour-plots.
I'll try to describe it through a reproducible example.

I am using gnuplot 4.2 patchlevel 6.

*** DESCRIPTION AND REPRODUCIBLE EXAMPLE ***

- SURFACE PLOT and CONTOUR PLOT

set style line 2 lc rgb "black" lw 2 lt 1
set style line 3 lc rgb "orange" lw 2 lt 4
set style increment user

set iso 30
set hidden
set contour both

f(x,y) = exp(-(x**2 + y**2))*cos(x/4)*sin(y)*cos(2*(x**2+y**2))
splot [-2:2][-2:2] f(x,y)

set terminal postscript color enhanced
set output "case_3D.ps"
replot

What do we get here?
- the 3D plot is fine (red and solid line, I did not touch it infact)
- the first color contour is solid, width = 2, but is RED, not BLACK
(despite having indicated lc rgb "black")
- the second color contour is dotted, width = 2, but is PINK, not
ORANGE
- the key (legend) is surprisingly right, showing a black solid and an
orange dotted sample lines which do not exist in the contour plot
proper.

I am confused here: it seems that if I specify the line style, that
determines also the color, overriding my specifications.

*** GNUPLOT VERSION ***

gnuplot> show version long

       G N U P L O T
       Version 4.2 patchlevel 6
       last modified Sep 2009
       System: Linux 2.6.18-164.6.1.el5

Compile options:
-READLINE  +LIBREADLINE  +HISTORY  +BACKWARDS_COMPATIBILITY  +BINARY_DATA
-LIBGD
-NOCWDRC  +X11  +X11_POLYGON  +MULTIBYTE  +USE_MOUSE  +HIDDEN3D_QUADTREE
+DATASTRINGS  +HISTOGRAMS  +OBJECTS  +STRINGVARS  +MACROS  +IMAGE

DRIVER_DIR     = "/usr/local/libexec/gnuplot/4.2"
GNUPLOT_PS_DIR = "/usr/local/share/gnuplot/4.2/PostScript"
HELPFILE       = "/usr/local/share/gnuplot/4.2/gnuplot.gih"

*** ***

Thank you for your help.

Adhemar