Generates a digital Butterworth filter using the sampling frequency, low cutoff frequency, high cutoff frequency, order, and filter type by calling the Butterworth Coefficients VI. Details
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filter type specifies the passband of the filter.
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X is the input signal to be filtered. | ||||||||
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sampling freq: fs is the sampling frequency and must be greater than zero. The default is 1.0. If it is less than or equal to zero, the VI sets Filtered X to an empty array and returns an error. | ||||||||
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high cutoff freq: fh is the high cutoff frequency. The VI ignores this parameter when filter type is 0 (Lowpass) or 1 (Highpass). When filter type is 2 (Bandpass) or 3 (Bandstop), high cutoff freq: fh must be greater than low cutoff freq: fl. | ||||||||
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low cutoff freq: fl is the low cutoff frequency and must observe the Nyquist criterion. The default is 0.125. where
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order must be greater than zero. The default is 2. If order is less than or equal to zero, the VI sets Filtered X to an empty array and returns an error. | ||||||||
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init/cont controls the initialization of the internal states. When init/cont is FALSE (default), the internal states are initialized to zero. When init/cont is TRUE, the internal filter states are initialized to the final filter states from the previous call to this instance of this VI. To filter a large data sequence that has been split into smaller blocks, set this control to FALSE for the first block and to TRUE for continuous filtering of all remaining blocks. | ||||||||
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Filtered X is the output array of filtered samples. | ||||||||
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error returns any error or warning from the VI. Refer to Signal Processing Error Codes for more information about these conditions. |
After calling the Butterworth Coefficients VI, the Butterworth Filter VI then calls the IIR Cascade Filter VI to filter the X sequence using this model to get a Butterworth Filtered X sequence. Refer to Butterworth Filters for more information about Butterworth filters.