HP 39gs Master Manual page 199

ROWNORM(<matrix>)
Finds the row norm of a matrix: the maximum, over all rows contained
in the matrix, of the absolute values of the sum of the elements in each
row.
Eg. For the matrix M 1
=
RREF(<matrix>)
This function takes an augmented matrix of size n by n+1 and transforms it into reduced row echelon form,
with the final column containing the solution.
Eg. The system of equations
is written as the augmented matrix
which is then stored as a 3x4 real matrix
We now use the function
form and store it as .
M2
This gives the final result shown in the matrix
solution of (1, -2, 3).
The huge advantage of this function is that it allows for inconsistent
matrices which can't be solved by an inverse matrix.
⎡ ⎤
1 2 3
⎢ ⎥
, the row with the largest absolute sum of 15 is row 2.
4 5 6
⎢ ⎥
⎢ ⎥ ⎦
⎣ −1
5 4
− 2 + z =
14 ⎫
x y 3
+ − = − 3 ⎬
2x y z
− + z =
4 x 2 y 2
−
⎡ 1
2
⎢
⎢ 2 1
⎢ 4
−
⎣
2
.
M1
to change this to reduced row echelon
RREF
M2
⎪
⎪
14 ⎭
14 ⎤
3
−3 ⎥ ⎥
−
1
14 ⎥ ⎦
2
on the right, giving a
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