HP 38g Graphing Calculator - Manual (Page 134)

To display a
matrix
In Home, enter the name of the matrix variable and press
I
enter !.
In the Matrix catalog (■ [MATRIX]), highlight the matrix
name and press {{EDIT}}.
To display one In Home, enter matrixname(roLU,column). For example, if M2
element is {{3,4,},[5,6]], then M2 ( 1 , 2 ) [ enter | returns 4.
To delete a
matrix In the Matrix catalog (■ [MATRIX]), highlight the matrix to
delete and press | del |. The name remains. The matrix is
redimensioned to 1X1 with a zero element.
To delete all In the Matrix catalog (■ [MATRIX]), press ■ [CLEAR].
matrices
To delete a Pressing | del | clears one row or column in a matrix. (Tou are
row or column prompted to choose.)
To transmit a You can send and receive matrices to/from other calculators
matrix just as you can send and receive aplets, programs, lists, and
notes.
After aligning the calculators’ infrared ports, open the Matrix
catalogs on both calculators. Highlight the matrbt to send,
then press {{SEND}} on the sending calculator and {{RECV}}
on the receiving calculator. See "Sending and Receiving
Aplets," in chapter 1.
6-4 Using Matrices