# MatrixMul

AnalysisLibErrType MatrixMul (void *matrixX, void *matrixY, int numberOfRowsInX, int colsRowsInXY, int numberOfColumnsInY, void *outputMatrix);

## Purpose

Multiplies two 2D input matrices, X and Y. MatrixMul obtains the (i, j)th element of the output matrix, Z, using the formula:

i = matrix row index
j = matrix column index
k = number of columns/rows in X/Y

Ensure that the matrix sizes are valid for matrix multiplication. You must meet the following size constraints:

- matrixX must be n by k.
- matrixY must be k by m.
- outputMatrix must be n by m.

### Example

/* Multiply two matrices. Note: A x B - B x A, in general. */
double x[10][20], y[20][15], z[10][15];
int n, k, m;
n = 10;
k = 20;
m = 15;
MatrixMul (x, y, n, k, m, z);

## Parameters

Input
Name | Type | Description
matrixX | numeric array | First matrix to multiply. The number of columns in matrixX must match the number of rows in matrixY. This matrix must be an array of doubles.
matrixY | numeric array | Second matrix to multiply. The number of columns of matrixX must match the number of rows of matrixY. This matrix must be an array of doubles.
numberOfRowsInX | integer | Number of rows in matrixX.
colsRowsInXY | integer | Number of columns in matrixX, which must be equal to the number of rows in matrixY.
numberOfColumnsInY | integer | Number of columns in matrixY.
Output
Name | Type | Description
outputMatrix | numeric array | Result of the matrix multiplication, as an array of doubles.

## Return Value

Name | Type | Description
status | AnalysisLibErrType | A value that specifies the type of error that occurred. Refer to analysis.h for definitions of these constants.