About matrix...



Hi,

I know the command 'echelon(%)' to calculate the echelon form of a matrix.
But what about the form 'small echelon'? 

I sho what I mean because I don't know the english translation

for exemple:

The matrix A:

[ -2    -5      8       0       17]
[1      3       -5      1       5]
[3      11      -19     7       1]
[1      7       -13     5       -3] 

echelon(A):

[1      3       -5      1       5]
[0      1       -2      2       -7]
[0      0       0       -4      20]
[0      0       0       0       0]


and what I want is something like small_echelon(A):

[1      0       1       0       1]
[0      1       -2      0       3]
[0      0       0       1       -5]
[0      0       0       0       0]

I need this form to calculate Nul(A).

Thank you for your help!

Patrick