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Designs and implements an IIR filter whose magnitude-squared response is inversely proportional to frequency over a specified frequency range. This inverse-f filter is typically used to colorize spectrally flat, or white, noise. The data type you wire to the X input determines the polymorphic instance to use.

Use the pull-down menu to select an instance of this VI.

Select an instance Inverse f Filter (DBL)Inverse f Filter (CDB)

Inverse f Filter (DBL)

	reset forces the filter coefficients to be redesigned and the internal filter states to be reset to zero when it is TRUE. The default is FALSE.
	X is the input array of samples to filter.
	fs specifies the design sample rate in samples/second.
	exponent specifies the exponent of the desired inverse-f spectral shape. This VI designs a digital filter with the desired magnitude-squared response of 1/frequencyexponent.
	filter specifications specifies the operating frequency range and the filter order of the filter. lower cutoff freq specifies the lower frequency edge of the operating frequency range of the filter. higher cutoff freq specifies the higher frequency edge of the operating frequency range of the filter. order specifies the number of first order stages of the inverse-f filter. Increasing order improves the inverse-f spectral shape but requires more computation time during filter operation.
	unity gain freq specifies the frequency in radians per second at which the ideal inverse-f filter response has unity gain. The actual inverse-f filter is designed to approximate the ideal filter over the frequency range defined by filter specifications. Therefore, the actual gain of the filter at unity gain freq is near unity only if unity gain freq is within the design frequency range specified in filter specifications.
	Filtered X is the output array of filtered samples.
	filter information returns the magnitude and phase of the frequency response of the designed inverse-f filter. magnitude returns the magnitude of the frequency response of the designed inverse-f filter in dB. frequency returns the frequencies of the frequency response of the designed inverse-f filter in Hz. magnitude returns the magnitudes of the frequency response of the designed inverse-f filter in dB. phase returns the phase of the frequency response of the designed inverse-f filter in degrees. frequency returns the frequencies of the frequency response of the designed inverse-f filter in Hz. phase returns the phases of the frequency response of the designed inverse-f filter in degrees.
	magnitude error returns the magnitude of the deviation of the actual inverse-f filter in dB when measured against the ideal inverse-f filter. The ideal filter has a magnitude-squared response proportional to 1/f exponent over the frequency range specified by filter specifications. frequency returns the frequencies of the magnitude error in Hz. magnitude returns the magnitudes of the magnitude error in dB.
	error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.
	noise bandwidth returns the expected noise bandwidth of the designed inverse-f filter.

Inverse f Filter (CDB)

	reset forces the filter coefficients to be redesigned and the internal filter states to be reset to zero when it is TRUE. The default is FALSE.
	X is the input array of samples to filter.
	fs specifies the design sample rate in samples/second.
	exponent specifies the exponent of the desired inverse-f spectral shape. This VI designs a digital filter with the desired magnitude-squared response of 1/frequencyexponent.
	filter specifications specifies the operating frequency range and the filter order of the filter. lower cutoff freq specifies the lower frequency edge of the operating frequency range of the filter. higher cutoff freq specifies the higher frequency edge of the operating frequency range of the filter. order specifies the number of first order stages of the inverse-f filter. Increasing order improves the inverse-f spectral shape but requires more computation time during filter operation.
	unity gain freq specifies the frequency in radians per second at which the ideal inverse-f filter response has unity gain. The actual inverse-f filter is designed to approximate the ideal filter over the frequency range defined by filter specifications. Therefore, the actual gain of the filter at unity gain freq is near unity only if unity gain freq is within the design frequency range specified in filter specifications.
	Filtered X is the output array of filtered samples.
	filter information returns the magnitude and phase of the frequency response of the designed inverse-f filter. magnitude returns the magnitude of the frequency response of the designed inverse-f filter in dB. frequency returns the frequencies of the frequency response of the designed inverse-f filter in Hz. magnitude returns the magnitudes of the frequency response of the designed inverse-f filter in dB. phase returns the phase of the frequency response of the designed inverse-f filter in degrees. frequency returns the frequencies of the frequency response of the designed inverse-f filter in Hz. phase returns the phases of the frequency response of the designed inverse-f filter in degrees.
	magnitude error returns the magnitude of the deviation of the actual inverse-f filter in dB when measured against the ideal inverse-f filter. The ideal filter has a magnitude-squared response proportional to 1/f exponent over the frequency range specified by filter specifications. frequency returns the frequencies of the magnitude error in Hz. magnitude returns the magnitudes of the magnitude error in dB.
	error returns any error or warning from the VI. You can wire error to the Error Cluster From Error Code VI to convert the error code or warning into an error cluster.
	noise bandwidth returns the expected noise bandwidth of the designed inverse-f filter.