Hi there I'm just putting this out there with the hope that someone will know how best to tackle this. I have a plot to do and I was wondering how to proceed. I'll have a matrix file like so 
1 1 20
1 2 45
1 3 46
2 1 45
etc ...

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If one imagines the first two columns as 'objects' the third column is a measure of similarity between those two objects. I want to create a 2D grid as an image (.png/.ps file or similar) - it will probably be about 40 squares by 40 squares in size. I would like the measure of similarity between the two objects to be highlighted as a specific colour and the objects to become the 'x' 'y' co-ordinates of the matrix. Any pointers in the right direction would be appreciated.

In reply to matrix 'graphic' problem by Angharad

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