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Computes the aggregate power in the range. The SVL Power in Band VI operates on Power, PSD, COP, and FFT [Mag] spectra. You can use this polymorphic VI to analyze a single spectrum or N spectra. The data type you wire to the spectrum input determines the polymorphic instance to use.

Details  

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

Select an instance SVFA Power in Band (1 Spectrum)SVFA Power in Band (N Spectra)

SVFA Power in Band (1 Spectrum)

	spectrum specifies the abscissa scaling and the magnitude of the spectrum. x0 specifies the start frequency or order of the spectrum. dx specifies the frequency or order resolution of the spectrum. magnitude specifies the magnitude of the spectrum.
	range defines the band of analysis. start specifies the lowest frequency or order of interest for the analysis band. The valid range is between 0 and the Nyquist frequency or order. Specify a value of -1 to select the lowest frequency or order as the minimum frequency or order of interest. stop specifies the highest frequency or order of interest for the analysis band. The valid range is between 0 and the Nyquist frequency or order. Specify a value of -1 to select the highest frequency or order as the maximum frequency or order of interest.
	spectrum info specifies properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Refer to Controlling Error Notification to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	power in band returns the aggregate power in the specified range.
	unit label returns the selected engineering units.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

SVFA Power in Band (N Spectra)

The SVFA Power in Band (N Ch) VI only accepts unscaled spectra.

	spectra specifies the data for each spectrum. spectrum specifies the abscissa scaling and the magnitude of the spectrum. x0 specifies the start frequency or order of the spectrum. dx specifies the frequency or order resolution of the spectrum. magnitude specifies the magnitude of the spectrum.
	range defines the band of analysis. start specifies the lowest frequency or order of interest for the analysis band. The valid range is between 0 and the Nyquist frequency or order. Specify a value of -1 to select the lowest frequency or order as the minimum frequency or order of interest. stop specifies the highest frequency or order of interest for the analysis band. The valid range is between 0 and the Nyquist frequency or order. Specify a value of -1 to select the highest frequency or order as the maximum frequency or order of interest.
	spectrum info specifies properties of the computed spectrum. The properties contained in spectrum info include channel name, spectrum type, spectrum scale as linear or dB, applied window, window size, FFT size, units, x-axis units, dB reference, applied weighting, peak units, and spectral density. Note  spectrum info must be connected when performing extended measurements. Do not modify the spectrum info values.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Refer to Controlling Error Notification to treat what is normally an error as no error or to treat a warning as an error. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	powers in band returns the aggregate powers in the specified ranges.
	unit labels returns the unit label for each channel.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

SVFA Power in Band Details

range specifies the band for which the power is computed. start and stop are coerced to the nearest spectrum bins.

You also can input spectra expressed in dB to the SVFA Power in Band VI. The spectra are converted to linearly-scaled spectra for the computation, and the results are converted back to logarithmically-scaled values for reporting.

This VI always returns power in band in EU^2rms or dB^rms.