contour plot of irregularly spaced data

[Don Fisher]

How does one form a regular two dimensional grid from
irregularly spaced data points?  The Matlab book says "If X
or Y is irregularly spaced, contour calculates contours
using a regularly spaced contour grid, then transforms the
data to X or Y", but I do not know how to accomplish this.

I would like to convert/interpolate the irregularly spaced
data samples to a grid and then contour that data.  Any code
fragments or pointers would be appreciated.

thanks
don
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|    Don Fisher                           address@hidden  |
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|    Tucson, AZ  85721                                            |             
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