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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)