Subtracts two single-precision vectors.


func vDSP_vsub(_ __B: UnsafePointer<Float>, _ __IB: vDSP_Stride, _ __A: UnsafePointer<Float>, _ __IA: vDSP_Stride, _ __C: UnsafeMutablePointer<Float>, _ __IC: vDSP_Stride, _ __N: vDSP_Length)



Single-precision real input vector.


Stride for B.


Single-precision real input vector.


Stride for A.


Single-precision real output vector.


Stride for C.


Number of elements to subtract.


This function calculates the differences of the first N elements of input vectors A and B, writing the result to output vector C:

A diagram showing the operation of the vDSP_vsub function. There are three rows. The top row represents the first input, vector A. The second row represents the second input, vector B. The bottom row represents the output, vector C. 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)
    C[n] = A[n] - B[n];

The following code shows an example of using vDSP_vsub(_:_:_:_:_:_:_:):

let stride = vDSP_Stride(1)

let a: [Float] = [1, 2, 3, 4, 5]
let b: [Float] = [10, 20, 30, 40, 50]

let n = vDSP_Length(a.count)

var c = [Float](repeating: 0,
                count: a.count)

vDSP_vsub(b, stride,
          a, stride,
          &c, stride,

// Prints "[-9.0, -18.0, -27.0, -36.0, -45.0]"

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