NAME

       rtf_create_bandpass_analytic  -  Creates an IIR filter estimating the analytic signal in a
       bandpass.

SYNOPSIS

       #include <rtf_common.h>

       hfilter rtf_create_bandpass_analytic(unsigned int nch, int proctype,
                                            double fl, double fh,
                                            unsigned int num_pole);

DESCRIPTION

       rtf_create_chebychev() creates a IIR chebychev filter processing nch channels of data type
       specified  by  proctype. The output of the filter is the analytic signal of the bandpassed
       data between the normalized frequencies fl and fh. The num_pole  parameter  specifies  the
       number of poles of the Chebychev filter used as the basis of the analytic filter.

       A  normalized  frequency  is  the  ratio  between  the absolute frequency and the sampling
       frequency (i.e. a value of 1.0 refers to the sampling frequency).

       The Z-transform of this filter has complex coefficients. So like rtf_create_filter(3)  the
       created filter will output complex values keeping the precision specified by proctype.

       It is important to note that this filter can quickly become unstable as the number of pole
       specified increased. Please refers to the authors of the library  to  know  the  stability
       domain (TODO: provides the stability domain here)

RETURN VALUE

       Returns the handle to the created filter in case of success, NULL otherwise.

SEE ALSO

       rtf_create_filter(3), rtf_destroy_filter(3)