man pages section 3: Multimedia Library Functions

## mlib_VectorMulMShift_S16_S16_Mod(3MLIB)

#### Name

mlib_VectorMulMShift_S16_S16_Mod, mlib_VectorMulMShift_S16_S16_Sat, mlib_VectorMulMShift_S16C_S16C_Mod, mlib_VectorMulMShift_S16C_S16C_Sat– multiplication of vector by matrix with shifting

#### Synopsis

```cc [ flag... ] file... -lmlib [ library... ]
#include <mlib.h>

mlib_status mlib_VectorMulMShift_S16_S16_Mod(mlib_s16 *z,
const mlib_s16 *x, const mlib_s16 *y, mlib_s32 m,
mlib_s32 n, mlib_s32 shift);```
```mlib_status mlib_VectorMulMShift_S16_S16_Sat(mlib_s16 *z,
const mlib_s16 *x, const mlib_s16 *y, mlib_s32 m,
mlib_s32 n, mlib_s32 shift);```
```mlib_status mlib_VectorMulMShift_S16C_S16C_Mod(mlib_s16 *z,
const mlib_s16 *x, const mlib_s16 *y, mlib_s32 m,
mlib_s32 n, mlib_s32 shift);```
```mlib_status mlib_VectorMulMShift_S16C_S16C_Sat(mlib_s16 *z,
const mlib_s16 *x, const mlib_s16 *y, mlib_s32 m,
mlib_s32 n, mlib_s32 shift);```

#### Description

Each of these functions multiplies a vector by a matrix and shifts the results.

For real data, the following equation is used:

```         m-1
z[i] = { SUM (x[j] * y[j*m + i]) } * 2**(-shift)
j=0```

where i = 0, 1, ..., (n - 1).

For complex data, the following equation is used:

```               m-1
z[2*i ]    = { SUM (xR*yR - xI*yI) } * 2**(-shift)
j=0

m-1
z[2*i + 1] = { SUM (xR*yI + xI*yR) } * 2**(-shift)
j=0```

where i = 0, 1, ..., (n - 1), and

```xR = x[2*j]
xI = x[2*j + 1]
yR = y[2*(j*m + i)]
yI = y[2*(j*m + i) + 1]```

#### Parameters

Each of the functions takes the following arguments:

z

Pointer to the first element of the destination vector.

x

Pointer to the first element of the source vector.

y

Pointer to the first element of the source matrix.

m

Number of rows in the matrix, and number of elements in the source vector.

n

Number of columns in the matrix, and number of elements in the destination vector.

shift

Right shifting factor.

#### Return Values

Each of the functions returns MLIB_SUCCESS if successful. Otherwise it returns MLIB_FAILURE.

#### Attributes

See attributes(5) for descriptions of the following attributes:

ATTRIBUTE TYPE

ATTRIBUTE VALUE

Interface Stability

Committed

MT-Level

MT-Safe