---
title: vDSP_ztocD
framework: accelerate
role: symbol
role_heading: Function
path: accelerate/vdsp_ztocd
---

# vDSP_ztocD

Copies the contents of a split double-precision complex vector to an interleaved vector.

## Declaration

```occ
extern void vDSP_ztocD(const DSPDoubleSplitComplex *__Z, vDSP_Stride __IZ, DSPDoubleComplex *__C, vDSP_Stride __IC, vDSP_Length __N);
```

## Parameters

- `__Z`: The split-complex input vector.
- `__IZ`: The distance between the elements in the input vector.
- `__C`: The interleaved-complex output vector.
- `__IC`: The distance between the real elements in the output vector. For example, a stride of 2 corresponds to a single complex element.
- `__N`: The number of complex elements that the function processes.

## Discussion

Discussion For example, the following code converts the contents of a DSPDoubleSplitComplex structure to an array of DSPDoubleComplex structures :     let srcReal = UnsafeMutableBufferPointer<Double>.allocate(capacity: 4)     _ = srcReal.initialize(from: [1.0, 2.0, 3.0, 4.0])          let srcImag = UnsafeMutableBufferPointer<Double>.allocate(capacity: 4)     _ = srcImag.initialize(from: [10.0, 20.0, 30.0, 40.0])          var source = DSPDoubleSplitComplex(realp: srcReal.baseAddress!,                                        imagp: srcImag.baseAddress!)          let destination = [DSPDoubleComplex](unsafeUninitializedCapacity: 4) {         buffer, initializedCount in                  vDSP_ztocD(&source, 1,                    buffer.baseAddress!, 2,                    4)                  initializedCount = 4     }          // Prints:     //     "[ DSPComplex(real: 1.0, imag: 10.0),     //        DSPComplex(real: 2.0, imag: 20.0),     //        DSPComplex(real: 3.0, imag: 30.0),     //        DSPComplex(real: 4.0, imag: 40.0) ]".     print(destination)

## See Also

### Converting split-complex vectors to interleaved-complex vectors

- [vDSP_ztoc](accelerate/vdsp_ztoc.md)