gradient map from n-by-n array

I have a n-by-n array which starts in the south-west corner. Each line is W-E and the next line is immediately north of it. If it helps the range of the values in the array is -76 to -30. I would like to plot a colour-gradient map for those values. Where do I start?

[Guillaume]

Huh? This, for example, is an array in matlab:

a = [1 6  11 16 21
     2 7  12 17 22
     3 8  13 18 23 
     4 9  14 19 24
     5 10 15 20 25];

What is the "start" of this array? What is a "line" in this array? What is a "colour-gradient map"?

Answer 1

[Walter Roberson]

pcolor() perhaps ? Though I am not sure what you mean by a color gradient map. Perhaps you want to use https://www.mathworks.com/help/images/ref/imgradient.html or https://www.mathworks.com/help/images/ref/imgradientxy.html