You are here: NI Home > Support > Product Reference > Manuals > LabVIEW 8.2 Help

Takes a signal in, finds the single tone with the highest amplitude or searches a specified frequency range, and returns the single tone frequency, amplitude, and phase. The data type you wire to the time signal in input determines the polymorphic instance to use. Details  Examples

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

Select an instanceExtract Single Tone Information 1 ChanExtract Single Tone Information N Chan

Extract Single Tone Information 1 Chan

	time signal in is the time-domain waveform.
	export signals selects the signal to export to exported signals. 0 none—Fastest computation 1 input signal 2 detected signal—Single sine tone 3 residual signal—Signal minus tone
	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. 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.
	advanced search controls the frequency domain search area, center frequency, and width. You use advanced search for narrowing the single tone search range. approx freq. is the center frequency used of the frequency domain search for the single sine tone. search is the frequency width, as a percentage of the sampling rate, for the frequency domain search for the single sine frequency.
	exported signals contains the signals specified by export signals. exported time signal is the waveform containing the exported time signal as selected by export signals. exported spectrum (dB) is the spectrum of the exported time signal as selected by export signals. f0 is the start frequency of the spectrum expressed in hertz. df is the frequency resolution of the spectrum expressed in hertz. dB Spectrum (Hann) is the magnitude spectrum of the (Hanning) windowed input signal expressed in dB.
	detected frequency is the frequency of the detected single sine tone in Hz.
	detected amplitude is the amplitude of the detected single sine tone in Vp.
	detected phase is the phase of the detected single sine tone in degrees.
	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.
	measurement info returns information about your measurement, mainly warnings for inconsistencies in your input signal. uncertainty is reserved for future use. Warning is TRUE if a warning is generated during processing. comments contains a warning message when Warning is true.

Extract Single Tone Information N Chan

The waveform array input should be the result of a multichannel acquisition where each element of the array of waveforms is a distinct and separate channel of data.

	time signals in is an array of time-domain waveforms.
	export signals selects the signal to export to exported signals. 0 none—Fastest computation 1 input signal 2 detected signal—Single sine tone 3 residual signal—Signal minus tone
	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. 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.
	advanced search controls the frequency domain search area, center frequency, and width. You use advanced search for narrowing the single tone search range. approx freq. is the center frequency used of the frequency domain search for the single sine tone. search is the frequency width, as a percentage of the sampling rate, for the frequency domain search for the single sine frequency.
	exported signals is an array of exported signals. exported time signal is the waveform containing the exported time signal as selected by export signals. exported spectrum (dB) is the spectrum of the exported time signal as selected by export signals. f0 is the start frequency of the spectrum expressed in hertz. df is the frequency resolution of the spectrum expressed in hertz. dB Spectrum (Hann) is the magnitude spectrum of the (Hanning) windowed input signal expressed in dB.
	detected frequencies is an array of frequencies of the detected single sine tone in Hz for each waveform.
	detected amplitudes is an array of amplitudes of the detected single sine tone in Vp for each waveform.
	detected phases is an array of phases of the detected single sine tone in degrees for each waveform.
	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.
	measurements info is an array that returns information about your measurement, mainly warnings for inconsistencies in your input signal. uncertainty is reserved for future use. Warning is TRUE if a warning is generated during processing. comments contains a warning message when Warning is true.

Extract Single Tone Information Details

This VI is designed to process a single channel or multiple channels continuously, typically from within a For Loop or a While Loop.

Examples

Refer to the following VIs for examples of using the Extract Single Tone Information VI:

• labview\examples\measure\resample_align_xmpl.llb\Correct for MIO inter-channel delay (continuous).vi

   

• labview\examples\measure\maxmpl.llb\Basic Single Tone Measurements.vi

   

• labview\examples\measure\maxmpl.llb\Advanced Single Tone Measurements.vi