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Generates the set of filter coefficients to implement a digital elliptic IIR filter.

You can pass these coefficients to the IIR Cascade Filter VI.

Details  

	filter type specifies the passband of the filter. 0 Lowpass 1 Highpass 2 Bandpass 3 Bandstop
	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 IIR Filter Cluster to an empty array and returns an error.
	high cutoff freq: fh is the high cutoff frequency. The default is 0.45. 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 and observe the Nyquist criterion.
	low cutoff freq: fl is the low cutoff frequency and must observe the Nyquist criterion. 0 f1< 0.5fs where f1 is the cutoff frequency, and fs is the sampling frequency. If low cutoff freq : fl is less than zero or greater than half the sampling frequency, the VI sets IIR Filter Cluster to an empty array and returns an error. The default is 0.125. Note  All cutoff frequencies must be less than half fs.
	passband ripple is the ripple in the passband. passband ripple must be greater than 0 and expressed in decibels. The default is 1.0. If passband ripple is less than or equal to 0, the VI sets the output filter data to 0 and returns an error.
	order is the order of the IIR filter and must be greater than zero.
	stopband attenuation is the attenuation in the stopband. stopband attenuation must be greater than zero and you must express it in decibels. The default is 60.0. If stopband attenuation is less than or equal to zero, the VI sets IIR Filter Cluster to an empty array and returns an error.
	IIR Filter Cluster contains the cascaded form of IIR filter coefficients. filter structure indicates either IIR second-order or IIR fourth-order filter stages. Reverse Coefficients is the reverse coefficients of the IIR cascade filter. Forward Coefficients is the forward coefficients of the IIR cascade filter.
	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.

Elliptic Coefficients Details

The Elliptic Coefficients VI is a subVI of the Elliptic Filter VI.