Applications :: Array In Mathematica Or R?

I have a 122x122 matrix saved as a .csv file. The values in each cell range from about -2 to +19 and I'm trying to incorporate a colors gradient were depending on the value the cell is assigned a separate color. Another option would be using a 3 column data set and attempting a listplot where the first two points plot the point an the third somehow assigns the color.

Mathematica would be ideal, since I am relatively familiar with the software, though if R is going to b easier, I'm open to exploration- I'll just need more instruction.

Edit: I think one of the Excel surface plots may also work. When I create it though, it groups all of the cell values in 3 different ranges. Is there a way for me to change this so I can have quite a few more, and preferably be able to dictate the color for each range.