How to plot a ScatterPlot with different colours for each column?

I have two 2 x 40 matrices A and B.

I would like each column in A and B to have the same colour on the scatter plot (i.e only 2 points on the plot having the same colour). For some reason the colours are being repeated for multiple colums. Or perhaps these colours are different but difficult to distinguish visually.

How do I plot the data such that each column have a unique visually distinguishable colour?

A=rand(2,40);
B=rand(2,40);

scatter(A,B,'filled')

Answer 1

[Chunru]

A=rand(2,40);
B=rand(2,40);
%scatter(A,B,'filled')
scatter(A', B', 'filled')  % use coloumn oriented data