Matrix n x n with n is integer

this is my homework: Write a function called mat_extract that takes two inputs: a matrix N and a scalar nonnegative integer n, in that order, where each dimension of N is greater than or equal to n. The function returns the n-by-n square array at the top right corner of N.

I need help with explain the last sentence ( what is it required me to do). I was confused with it because my English was bad

[James Tursa]

+1 For telling us up front this is homework.

Answer 1

[James Tursa]

Examples,

If N is a 5x7 matrix and n is 3, then your function would return N(1:3,5:7), the 3x3 sub-matrix at the top right corner.

If N is a 123x29 matrix and n is 5, then your function would return N(1:5,25:29), the 5x5 sub-matrix at the top right corner.

Etc.

So you need to write code that is generic and will do this for any matrix N and integer n.

Hint: Look at the size( ) function to get the dimensions of N.

[David]

Hi, Its is extremely helpful for me. I understand your example and it really helpful. One last question is that could I set the matrix N is the random 6x6 matrix ?? I always have questions if the question is not clear.

[Steven Lord]

The person using your code (in this case most likely the person grading your assignment, your professor and/or their teaching assistants) will pass whatever they choose into your function as N. Your function should be general enough to handle any N and n where N has at least n rows and at least n columns.

If this weren't a homework assignment you'd probably want to include code to check that N has at least n rows and at least n columns, but you can (probably) trust your professor.