## \$%MTXMUL^MATH

### M[UMPS] by Example

Approved for inclusion in a future M[UMPS] language standard as part of the library for Matrix Mathematics.

This function multiplies two matrices, and returns the result in a third matrix. The result matrix may not be either of the source matrices.

Assuming that the matrices DEMO and INV are as in the example with the function MTXINV, then the function call

Set X=\$%MTXMUL^MATH(.DEMO,.INV,.R,4,4,4)

will return the value 1 in X and as matrix R:

```1   0   0   0
0   1   0   0
0   0   1   0
0   0   0   1
```

Assuming that the matrices A and B contain:

```        A                        B
1    2   –1    0           3    1    2
4    0    2    1          –4    5   –2
2   –5    1    2           1    0    3
2    3   –1
```

then the function call Set X=\$%MTXMUL^MATH(.A,.B,.R,3,4,3) will return the value 1 in X and as the matrix R:

``` –6   11   –5
16    7   13
31  –17   15
```

The MDC has approved code to approximate the return value of this function. Implementors are encouraged to provide more accurate and efficient code).