Colour fill contour plots

[Morwenna Griffiths <morwenna.griffiths(at)sci.monash.edu.au>]

I am wanting to do two colour fills on a single plot, but can't seem to
get a "transparent" colour.

I can colour in between just the values I want with something like
contour,b,levels=findgen(20)*10
contour,a,levels=[70,80],c_col=[250,0],/fill,/over
but then this blacks (background colour) in all values of a over 80.

I have tried
contour,a,levels=[70,80],c_col=[250],/fill,/over
but this fills all values over 70 with my required colour.

What I want to do is to fill between 70 and 80 with a particular colour
but leave the rest of the plot
unchanged.

Any ideas?

Morwenna

--
Morwenna Griffiths
Department of Mathematics and Statistics,
P.O. Box 28M,
Monash University,
Vic. 3800,
Australia

Email: morwenna.griffiths@sci.monash.edu.au
Web page: http://www.maths.monash.edu.au/~morwenna

Phone:   (03) 9905 4411

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