Code to zero the elements above major diagonal

Hi, I’m finding an inverse of a matrix using Gaussian elimination. So, the first step is that I had to carry out row operations zero the elements below the diagonal and that has no problem with me. The problem is I don’t know what code I need to write on the script to zero the elements above the major diagonal. If I could get an answer for that it would be very great. Thank you.

[James Tursa]

Please post your code and then tell us what steps you are doing or output you are getting that you think needs fixing.

Answer 1

[madhan ravi]

Example:

A = ones(4)

B = tril(A) 

Or

B= tril(A,1)

[madhan ravi]

The above answer makes the upper triangular matrix zero

[Tiny Rick]

Do you have a specific formula to be written as a code to carry out the row operations?

[madhan ravi]

you mean rref? example of your output is there in my answer?

Answer 2

[Tiny Rick]

What I mean is there are values for the elements above the diagonal let’s say a matrix;

[5 7 9;0 4 2;0 0 3]

Do you have a formula that can be to carry out the row operations so that we can reduce the elements above the diagonal to zero? And It can accept any size of matrix

[Steven Lord]

Since this is almost certainly a homework assignment, your textbook probably has some pseudocode you can adapt into a function.

If this is not a homework assignment, don't invert and/or use Gaussian elimination. Use the backslash operator \ to solve your linear system of equations, or (if you absolutely must compute the inverse) use the inv function.