Is there an easy way to divide each matrix element by the column sum? For example:
input:
1 4
4 10
output:
1/5 4/14
4/5 10/14
Here's a list of the different ways to do this ...
... using bsxfun
:
B = bsxfun(@rdivide,A,sum(A));
... using repmat
:
B = A./repmat(sum(A),size(A,1),1);
... using an outer product (as suggested by Amro):
B = A./(ones(size(A,1),1)*sum(A));
... and using a for loop (as suggested by mtrw):
B = A;
columnSums = sum(B);
for i = 1:numel(columnSums)
B(:,i) = B(:,i)./columnSums(i);
end
Update:
As of MATLAB R2016b and later, most built-in binary functions (list can be found here) support implicit expansion, meaning they have the behavior of bsxfun
by default. So, in the newest MATLAB versions, all you have to do is:
B = A./sum(A);