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InverseFastFourierTransform

Calculate a time-domain signal from its frequency representation using the inverse Fast Fourier Transform (IFFT).

This node will replace the original (e.g., frequency) axis of the data by a time axis, carrying over the axis label, if any. More Info... Version 1.0.0

Ports/Properties

data

Data to process.

  • verbose name: Data
  • default value: None
  • port type: DataPort
  • value type: AnyNumeric (can be None)
  • data direction: INOUT

axis

Axis along which the IFFT will be calculated. You can also enter the axis label here as in frequency.mylabel. If the data is not a packet, any named axis will translate to -1.

  • verbose name: Axis
  • default value: frequency
  • port type: ComboPort
  • value type: str (can be None)

n

Length of the output axis, in samples. Note that if this is given and differs from the size of the input, the input is either cropped or zero-padded. In the latter case, this can give unexpected results; please see the documentation of the numpy FFT algorithm for details.

  • verbose name: Output Size
  • default value: None
  • port type: IntPort
  • value type: int (can be None)

normalization

Normalization to apply to the FFT. Backward means that the forward FFT is unscaled and the corresponding inverse FFT is scaled by 1/n. Ortho means that both the forward and inverse FFT are scaled by 1/sqrt(n). Forward means that the forward FFT is scaled by 1/n and the corresponding inverse FFT is unscaled.

  • verbose name: Normalization
  • default value: backward
  • port type: EnumPort
  • value type: str (can be None)

onesided

Assume one-sided spectrum. If this is set, the input must be a one-sided (and complex-valued) spectrum, and the output will be a real-valued signal. Otherwise the output will be a complex-valued signal. This is equivalent to the RFFT / IRFFT distinction in numerical subroutines, e.g., numpy.

  • verbose name: Assume One-Sided Spectrum
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

partition_axis

Axis along which to partition the computation. This can be used to reduce the memory requirements on large data.

  • verbose name: Partition Axis
  • default value: disabled
  • port type: ComboPort
  • value type: object (can be None)

num_partitions

Number of partitions to use. The memory usage is divided by this amount. Requires that partition_axis is set to something other than disabled.

  • verbose name: Num Partitions
  • default value: 4
  • port type: IntPort
  • value type: int (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

  • verbose name: Set Breakpoint (Debug Only)
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

  • verbose name: Metadata
  • default value: {}
  • port type: DictPort
  • value type: dict (can be None)