Getting Error: Undefined function 'colspace' for input arguments of type 'double'.

Question: Find column space of row reduced echelon form of the matrix A = magic(6).

My Matlab Code:

>> A = [2 -1 0 0 0; -1 2 -1 0 0; 0 -1 -2 -1 0; 0 0 -1 2 -1; 0 0 0 -1 2]

A =

       2    -1     0     0     0
      -1     2    -1     0     0
       0    -1    -2    -1     0
       0     0    -1     2    -1
       0     0     0    -1     2

>> R = rref(A)

R =

       1     0     0     0     0
       0     1     0     0     0
       0     0     1     0     0
       0     0     0     1     0
       0     0     0     0     1

>> C = colspace(R)
Undefined function 'colspace' for input arguments of type 'double'.

Problem: I am getting the aforementioned error: Undefined function 'colspace' for input arguments of type 'double'. when I try to find the column space for the matrix (R). Please can you find the problem and help me out? I am new to Matlab and I am learning this software. Thanks a lot! Appreciate it. :)

MATLAB Version: MATLAB R2013a

Answer 1

[Azzi Abdelmalek]

colspace(sym(A))

[John]

Yes, it works! Thank you.