DensityPlot colours misbehaving
- To: mathgroup at smc.vnet.net
- Subject: [mg78705] DensityPlot colours misbehaving
- From: "Tim Birks" <pystab at hotmail.com>
- Date: Sat, 7 Jul 2007 06:05:16 -0400 (EDT)
- Organization: School of Physics, University of Bath, UK
I have Mathematica v6 and am running code that worked fine with v5. OS is
Windows XP. Here's a particularly annoying unexplained difference between
the two versions.
DensityPlot[Exp[-x], {x, 0., 4.}, {y, 0., 4.}, ColorFunctionScaling ->
False]
behaves as expected, giving a nice gradual horizontal grading of colour from
white on the left to blue/violet on the right.
In contrast,
DensityPlot[Exp[-x - y], {x, 0., 4.}, {y, 0., 4.}, ColorFunctionScaling ->
False]
which should give a similar grading from lower-left to upper-right, instead
gives a mostly blue/violet field with a pure white triangular wedge in the
lower-left corner. The discontinuous jump between the two occurs roughly
where x+y=1.4.
Re-plotting with x and y running from 0 to 2 instead of 4 makes the white
triangle appear smaller rather than bigger. Note the setting of
ColorFunctionScaling means that the colour at a particular point (x,y)
shouldn't depend on what's happening elsewhere; also note that the functions
plotted are very simple, well-behaved and evaluate to between 0 and 1 in the
ranges plotted.
Can anyone please explain what is happening, how it can be fixed, and why it
is not a bug?
Apologies if this has been asked before. I have searched the posts available
on my news reader and found nothing relevant.
T.
- Follow-Ups:
- Re: DensityPlot colours misbehaving
- From: Brett Champion <brettc@wolfram.com>
- Re: DensityPlot colours misbehaving
- From: Carl Woll <carlw@wolfram.com>
- Re: DensityPlot colours misbehaving