setting column of a matrix to zero

A(j,k) = exp((-a * j^2 * z)/mt(k))

A is a 20 by 50 matrix

how can i set column 25 - 30 of A to zero

thank you

Answer 1

[Bhaskar R]

a(:, 25:30) = 0;    % all columns from 25 to 30 assigned as 0's

Refer the link for the MATLAB matrix indexing

https://in.mathworks.com/company/newsletters/articles/matrix-indexing-in-matlab.html

Answer 2

[Muhammad Usman]

You haven't define constants a and z, and a vector mt, so I suppose a=-1, z=4 and mt=rand(1,50) and following lines of code to produce zeros in your required columns

a=-1; z=4;
mt=rand(1,50);
A=zeros(20,50);
for j=1:20
    for k=1:50
    A(j,k) = ((-a * j^2 * z)/mt(k));
    if k>=25 && k<=30
        A(j,k)=0;
    end
    end
end
A