HP 39gII User Manual page 216

Examples
Identity Matrix
Transposing a
Matrix
Reduced-Row
Echelon Form
206
You can create an identity matrix with the IDENMAT
function. For example, IDENMAT(2) creates the 2×2
identity matrix [[1,0],[0,1]].
You can also create an identity matrix using the MAKEMAT
(make matrix) function. For example, entering
J,4,4) creates a 4 × 4 matrix showing the
MAKEMAT(I
numeral 1 for all elements except zeros on the diagonal.
The logical operator (
number) and J (the column number) are equal, and returns
1 when they are not equal.
The TRN function swaps the row-column and column-row
elements of a matrix. For instance, element 1,2 (row 1,
column 2) is swapped with element 2,1; element 2,3 is
swapped with element 3,2; and so on.
For example, TRN([[1,2],[3,4]]) creates the matrix
[[1,3],[2,4]].
The following set of equations
can be written as the augmented matrix
1 2 – 3 14
1 – 3 –
2 1
4 2 – 2 14
which can then be stored
as a real matrix in
×
3 4
any matrix variable. M1 is
used in this example.
You can use the RREF
function to change this to
reduced row echelon form,
storing it in any matrix
variable. M2 is used in this
example.
) returns 0 when I (the row
x 2y – + 3z =
2x + y z – =
4x – 2y + 2z
14
– 3
= 14
Matrices