I'm using splus6(2) under windows 2000 to create color scatter-plots, in
which the colour plotted represents a third "z" variable with a warm-cold
colour gradation. The "image" function does this, but only seems to use a
limited color-palate, insufficient for a warm-cold representation.
I've tried expanding the palate using the options under "graph styles" and
"color schemes" under the options tab on the tool-bar with limited success.
Another possibility is to supply "z" to a routine which calculates the
appropriate RGB color mix using the bitwise OR operations described in the
PDF programmers guide, but this seems a long way round, and would tax me.
Does anyone know of a simpler way to achieve this ? Many thanks.
Jonathan Dakin, Imperial College London
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