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vDSP_vasbmD

Calculates the double-precision element-wise product of the sum of two vectors and the difference of two vectors, using the specified stride.

Declaration

extern void vDSP_vasbmD(const double *__A, vDSP_Stride __IA, const double *__B, vDSP_Stride __IB, const double *__C, vDSP_Stride __IC, const double *__D, vDSP_Stride __ID, double *__E, vDSP_Stride __IE, vDSP_Length __N);

Parameters

  • __A:

    The input vector A in E = (A + B) * (C - D).

  • __IA:

    The distance between the elements in the input vector A.

  • __B:

    The input vector B in E = (A + B) * (C - D).

  • __IB:

    The distance between the elements in the input vector B.

  • __C:

    The input vector C in E = (A + B) * (C - D).

  • __IC:

    The distance between the elements in the input vector C.

  • __D:

    The input vector D in E = (A + B) * (C - D).

  • __ID:

    The distance between the elements in the input vector D.

  • __E:

    The output vector E in E = (A + B) * (C - D).

  • __IE:

    The distance between the elements in the output vector E.

  • __N:

    The number of elements that the function processes.

Discussion

This function calculates the products of the first N elements of the addition of vectors A and B and the subtraction of vectors C and D.

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

[Image]

The following code shows an example of using this function:

    let stride = 1
    let count = 5
    
    let a: [Double] = [ 1,  2,  3,  4,  5]
    let b: [Double] = [10, 20, 30, 40, 50]
    let c: [Double] = [ 5,  4,  3,  2,  1]
    let d: [Double] = [50, 40, 30, 20, 10]
    
    
    let e = [Double](unsafeUninitializedCapacity: count) {
        buffer, initializedCount in
        
        vDSP_vasbmD(a, stride,
                     b, stride,
                     c, stride,
                     d, stride,
                     buffer.baseAddress!, stride,
                     vDSP_Length(count))
        
        initializedCount = count
    }
    
    // Prints "[-495.0, -792.0, -891.0, -792.0, -495.0]".
    print(e)

See Also

Quaternary add-subtract-multiply operations