MATLAB: Error ” Assignment has fewer non singleton rhs dimensions than non singleton subscripts”

MATLAB

Hello, I have 2 arrays that represent indexes of a matrix, for example idx =[ 1 5 ] and idy = [ 2 3] . When I execute this line
 M(idx,idy)=1; % M is a matrix
all the components M(1,2) M(1,3) M(5,2) and M(5,3) are affected . What can I do so that only M(1,2) and M(5,3) become equal to 1 ? ( without any loop)
N.B : I used sub2ind (size(M),idx,idy) but it's slow in my case ( not this example) because the matrix M is bigger.
Thank you in advance

Best Answer

Use sub2ind:
M(sub2ind(size(M),idx,idy)) = 1
@Elkhanssaa Marsali: you just edited your question to add this line "I used sub2ind (size(M),idx,idy) but it's slow in my case"
Well, using sub2ind is one solution, otherwise you could use a loop. It does not matter if you want a faster solution, those are the solutions for your problem. Well, I guess this is one answer that will never get accepted :)
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