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Hi,1. I set up for a fast Fourier transform of a real [Double] time domain signal of count numSamples:setupFFT = vDSP.FFT( log2n: vDSP_Length(log2(Float(numSamples))), radix: .radix2, ofType: DSPDoubleSplitComplex.self )2. I take the forward transform and get 2 [Double] arrays for real & imaginary spectral parts, each of count (numSamples/2):realParts.withUnsafeMutableBufferPointer { realPtr in imagParts.withUnsafeMutableBufferPointer { imagPtr in var complexSignal = DSPDoubleSplitComplex(realp: realPtr.baseAddress!, imagp: imagPtr.baseAddress!) xData.withUnsafeBytes { vDSP.convert( interleavedComplexVector: [DSPDoubleComplex]($0.bindMemory(to: DSPDoubleComplex.self)), toSplitComplexVector: &complexSignal ) } setupFFT?.transform(input: complexSignal, output: &complexSignal, direction: .forward) } }3. Lastly I take the inverse transform of the complex spectrum. The part that's tricky is getting real time domain signal from the complex parts:var outputData = [Double](repeating: 0.0, count: specSamples*2) realParts.withUnsafeMutableBufferPointer { realPtr in imagParts.withUnsafeMutableBufferPointer { imagPtr in var complexSignal = DSPDoubleSplitComplex(realp: realPtr.baseAddress!, imagp: imagPtr.baseAddress!) setupFFT?.transform(input: complexSignal, output: &complexSignal, direction: .inverse) // How do we use the Swift vDSP convert the split complex spectrum with N/2 complex samples // to a real time domain signal with N real samples? // This is what I imagine although it's not proper Swift: outputData.withUnsafeMutableBytes { outputPtr in vDSP.convert(splitComplexVector: complexSignal, toInterleavedComplexVector: outputPtr.baseAddress!.bindMemory(to: DSPDoubleComplex.self)) } } }Lines 10-12 do not compile, is there a proper casting and is this the best way to use the 2020 Swift vDSP enum? Thanks,Paul