Calculates the inner (conjugate) product of a single-precision complex vector.


func vDSP_zidotpr(_ __A: UnsafePointer<DSPSplitComplex>, _ __IA: vDSP_Stride, _ __B: UnsafePointer<DSPSplitComplex>, _ __IB: vDSP_Stride, _ __C: UnsafePointer<DSPSplitComplex>, _ __N: vDSP_Length)



Input vector A.


The stride within A. For example if stride is 2, every second element is used.


Input vector B.


The stride within B. For example if stride is 2, every second element is used.


The dot product (on return).


The number of elements to process.


The functions in this group calculate the dot product of two vectors, using the following operation:

C[0] = sum(A[n] * B[n], 0 <= n < N);

The following example shows how you calculate the luminosity of a color using the Rec. 709 luma coefficients for the color-to-grayscale conversion. Array a defines the color, 0xDa70D6, and array b defines the coefficients:

let a: [Float] = [0xDA, 0x70, 0xD6]
let b: [Float] = [0.2126, 0.7152, 0.0722]

Passing these values to vDSP_dotpr(_:_:_:_:_:_:) calculates the luminosity and writes the result to c:

let n = vDSP_Length(a.count)
var c: Float = .nan

let stride = vDSP_Stride(1)

vDSP_dotpr(a, stride,
           b, stride,

print(c)    // Prints "141.9"

See Also

Dot Product Calculation

static func dot<U>(U, U) -> Double

Returns the double-precision dot product of two vectors.

static func dot<U>(U, U) -> Float

Returns the single-precision dot product of two vectors.