IBM 5100 Basic Reference Manual page 131

(
Example
The following example shows execution of a MAT (inverse) statement:
20 DIM X(2,2). Y(2,2)
80 IF DET (Y)
=
0 GOTO 300
90 MAT X
=
INV (Y)
295 GOTO 310
300 PRINT 'SINGULAR MATRIX'
310 END
The resulting values are:
If Y is , then X is
2
2 -1
-1
127