Function

vDSP_vsmaD(_:_:_:_:_:_:_:_:)

Adds a double-precision vector to the product of a double-precision scalar value and a double-precision vector.

Declaration

func vDSP_vsmaD(_ __A: UnsafePointer<Double>, _ __IA: vDSP_Stride, _ __B: UnsafePointer<Double>, _ __C: UnsafePointer<Double>, _ __IC: vDSP_Stride, _ __D: UnsafeMutablePointer<Double>, _ __ID: vDSP_Stride, _ __N: vDSP_Length)

Parameters

__A

Double-precision real input vector.

__IA

Stride for A.

__B

Pointer to double-precision real input scalar.

__C

Double-precision real input vector.

__IC

Stride for C.

__D

Double-precision real output vector.

__ID

Stride for D.

__N

The number of elements to process.

Discussion

This function calculates the products of the first N elements of A and the scalar value B, adds each product to the corresponding value in C, and writes the result to D:

A diagram showing the operation of the vDSP_vsma function. There are five rows. The top two rows represents the first two inputs, vector A and scalar B. The third row represents the intermediate result of the first two inputs. The forth row represents the third input, vector C. The bottom row represents the output, vector D. The diagram has connecting lines from the input vectors to the output vector indicating the relationships between the inputs and output.

The operation is:

for (n = 0; n < N; ++n)
    D[n] = A[n]*B + C[n];

See Also

Ternary (Vector-Scalar-Vector) Multiply-Add Operations

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