Making the Y-axis a scale of a specific variable

How to change the scale of values of the y-axis to a scalar multiple of a specific variable? (i.e. I want to make all values that appear on the y-axis scale as scalar multiples of a varaible "r"). Thank you.

Answer 1

[the cyclist]

Here is one way:

r = 7;
m = 50;
N = 50;

x = rand(N,1);
y = m*rand(N,1);

figure
plot(x,y,'.');
set(gca,'YTick',0:r:max(y),'YTickLabel',0:r:max(y))