symmetrize

Functions

int main(int argc, char *argv[])

symmetrize [ option ] [ infile ]

• -l int

  • FFT length $(2\le L)$

• -q int

  • input format $(0\le Q\le 3)$

• -o int

  • output format $(0\le O\le 3)$

• infile str

  • double-type data sequence

• stdout

  • double-type symmetrized data sequence

ramp -l 3 | x2x +da
# 0, 1, 2
ramp -l 3 | symmetrize -l 4 -q 0 -o 1 | x2x +da
# 0, 1, 2, 1 (used for shaping fourier transform input)
ramp -l 3 | symmetrize -l 4 -q 0 -o 2 | x2x +da
# 1, 1, 0, 1, 1 (used for shaping frequency response)
ramp -l 4 | symmetrize -l 6 -q 0 -o 3 | x2x +da
# 2, 1, 0, 1, 2 (used for shaping frequency response)

Parameters:

• argc – [in] Number of arguments.

• argv – [in] Argument vector.

Returns:

0 on success, 1 on failure.

See also

transpose

class DataSymmetrizing

Symmetrize/desymmetrize data sequence.

The input and output takes one of the following forms.

Type 0:

$$\begin{array}{cccc}x(0),& x(1),& \dots ,& x(L/2).\end{array}$$

Type 1:

$$\begin{array}{ccccccc}x(0),& x(1),& \dots ,& x(L/2),& x(L/2-1),& \dots ,& x(1).\end{array}$$

Type 2:

$$\begin{array}{cccccccc}\frac{1}{2}x(L/2),& x(L/2-1),& \dots ,& x(0),& x(1),& \dots ,& x(L/2-1),& \frac{1}{2}x(L/2).\end{array}$$

Type 3:

$$\begin{array}{cccccccc}x(L/2),& x(L/2-1),& \dots ,& x(0),& x(1),& \dots ,& x(L/2-1),& x(L/2),\end{array}$$

where $L$ must be even.

Public Types

enum InputOutputFormats

Input and output format.

Values:

enumerator kStandard

enumerator kSymmetricForApplyingFourierTransform

enumerator kSymmetricForPreservingFrequencyResponse

enumerator kSymmetricForPlottingFrequencyResponse

enumerator kNumInputOutputFormats

Public Functions

DataSymmetrizing(int fft_length, InputOutputFormats input_format, InputOutputFormats output_format)

Parameters:

• fft_length – [in] FFT length, $L$.

• input_format – [in] Input format.

• output_format – [in] Output format.

inline int GetFftLength() const

Returns:

FFT length.

inline InputOutputFormats GetInputFormat() const

Returns:

Input format.

inline InputOutputFormats GetOutputFormat() const

Returns:

Output format.

inline int GetInputLength() const

Returns:

Expected input length.

inline int GetOutputLength() const

Returns:

Expected output length.

inline bool IsValid() const

Returns:

True if this object is valid.

bool Run(const std::vector<double> &data_sequence, std::vector<double> *symmetrized_data_sequence) const

Parameters:

• data_sequence – [in] Input data.

• symmetrized_data_sequence – [out] Output data.

Returns:

True on success, false on failure.