colored table

I want to print a table where table elements are colored according to the frequency of the bin.  For example, consider below table.

Function values that I would like to print in the table

                            x.eq.minus1  x.eq.zero  x.eq.plus1
y.eq.minus1             -20                 10            -5
y.eq.zero                 -10                  6             22
y.eq.plus1                -8                    10           -14


Frequency table to color the above table

                            x.eq.minus1  x.eq.zero  x.eq.plus1
y.eq.minus1             0.05             0.15           0.1
y.eq.zero                 0.07             0.3           0.08
y.eq.plus1                0.05            0.15           0.05


In the resulting table, the element for (x = 0, y = 0) will be 6.  This will be printed with a dark color background.  The element for (x = -1, y = -1) will be -20.  This will be printed with a light color background.  And so on.

Thanks for your help,
Naresh