There are more efficient ways to approach this, but probably the easiest is to use a for loop:
A= 200000;
APR= [4,5,6];
M= [36,48,60,72];
for k1 = 1:length(APR)
r = APR(k1)/1200;
P(k1,:)= (A.*r.*(1+r).^M)./(((1+r).^M)-1);
end
I am not certain what you want to do, but this is one solution. It uses ‘APR’ to define the array size, and computes ‘P’ for all values of ‘M’ for each value of ‘APR’.
Note that I completely vectorised your ‘P’ assignment. See the documentation for Special Characters, ‘Array Indexing’, Array vs. Matrix Operations, and for loops.
