question of applying sum() to the matrix with zero values

my matrix is X=[1 0 0 ;0 0 0;0 9 0](actual matrix is larger than this and having less values more zoros) my question is ,when applying sum(X),it gives error message "??? Subscript indices must either be real positive integers or logicals."

Answer 1

[Azzi Abdelmalek]

You've probably used sum as a variable in your code. Try this

clear sum
X=[1 0 0 ;0 0 0;0 9 0]
sum(X)

[mahesh chathuranga]

thank you very much.I'm newer for MATLAB.

[Image Analyst]

Be aware that sum will be over columns and will be a ax3 array. If you want the sum of the whole array, you can do this:

theSum = sum(X(:));

which turns X into a 1D vector before it gets summed. theSum will then be a scalar (single number) rather than a 1 by 3 array.

[mahesh chathuranga]

thank you very much for helping me.