---
title: vDSP_vsub
framework: Kernel
role: symbol
role_heading: Function
platforms: [macOS 10.0+]
path: kernel/1532189-vdsp_vsub
---

# vDSP_vsub

Subtracts two single-precision vectors.

## Declaration

```occ
void vDSP_vsub(const float *__B, vDSP_Stride __IB, const float *__A, vDSP_Stride __IA, float *__C, vDSP_Stride __IC, vDSP_Length __N);
```

## Parameters

- `__B`: The single-precision real input vector B.
- `__IB`: The stride for input vector B.
- `__A`: The single-precision real input vector A.
- `__IA`: The stride for input vector A.
- `__C`: The single-precision real output vector.
- `__IC`: The stride for output vector C.
- `__N`: Number of elements to subtract.

## Discussion

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

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,           n)

// Prints "[-9.0, -18.0, -27.0, -36.0, -45.0]". print(c)

## See Also

### Vector Arithmetic Functions

- [vDSP_vadd](kernel/1532191-vdsp_vadd.md)
- [vDSP_vma](kernel/1532193-vdsp_vma.md)
- [vDSP_vmul](kernel/1532206-vdsp_vmul.md)
- [vDSP_vsmul](kernel/1532223-vdsp_vsmul.md)
- [vDSP_vdiv](kernel/1532168-vdsp_vdiv.md)