Multiplication of column elements of a matrix

Hi

If I am having a marix of size "m*n"

I have to find the product of column elements of each row (But the number of columns selected for multiplication has to be user selected)

for example :

if the matrix is A=[1 2 3;4 5 6;7 8 9]

I want find the resultant vector containing [1 2*5*7 3*6] (multiplication of 1 element in the ist row, 2 elements in the second row, 3 elements in the 3rd row)

for this is have used the code

A=[1 2 3;4 5 6;7 8 9];

row_elemens=[1 3 2];

for i=1:3

result=prod(A(i,1:row_elemens(i)));

end

is there any simple solution for this problem without using any loop and with a single line

Answer 1

[Ameer Hamza]

Your question mentioned "without using any loop and with a single line". Try this

A=[1 2 3;4 5 6;7 8 9];
row_elemens=[1 3 2];

result = arrayfun(@(i) prod(A(i,1:row_elemens(i))), 1:3);

[Vinay Killamsetty]

Thank you very much

[Ameer Hamza]

I am glad to be of help.