sfilter_nonrec 

Performs filtering in lowpass, highpass, bandpass, or bandstop (notch) mode.

FORMAT

  SFILTER_NONREC (in, out, n, flow, fhigh, wiggles, nterms, [status])

Arguments

  in                  REAL*4
                      On entry, a one-dimensional array IN containing the
                      data to be filtered.
                      On exit, in is unchanged.

  out                 REAL*4
                      On entry, a one-dimensional array OUT containing the
                      filtered data.  The IN and OUT arrays can be the same
                      array.
                      On exit, out is overwritten and contains the filtered
                      data.

  n                   INTEGER*4
                      On entry, the number of values to be filtered; n > 2
                      and n<SP>>=<SP>2(nterms+1).
                      On exit, n is unchanged.

  flow                REAL*4
                      On entry, the lower frequency of the filter, given as a
                      fraction of the Nyquist sampling frequency
                      1/(2delta_t); 0.0<SP><=<SP>flow<SP><=<SP>1.0.
                      On exit, flow is unchanged.

  fhigh               REAL*4
                      On entry,  the upper frequency of the filter, given as
                      a fraction of the Nyquist sampling frequency
                      1/(2delta_t); 0.0<SP><=<SP>fhigh<SP><=<SP>1.0.
                      On exit, fhigh is unchanged.

  wiggles             REAL*4
                      On entry, a number in -dB units which is proportional
                      to the oscillation from the Gibbs phenomenon;
                      0.0<SP><=<SP>wiggles<SP><=<SP>500.0.
                      On exit, wiggles is unchanged.

  nterms              INTEGER*4
                      On entry, the order of the filter, that is, the number
                      of filter coefficients in the filter equation;
                      2<SP><=<SP>nterms<SP><=<SP>500 and
                      n<SP>>=<SP>2(nterms+1).
                      On exit, nterms is unchanged.

  status              INTEGER*4
                      On entry, an optional variable with an unspecified
                      value.
                      On exit, status is overwritten.  When the subroutine is
                      called, status is defined and its integer value
                      describes the status of the operation. The following
                      table shows the status function names, their associated
                      integer values, and the status description associated
                      with each integer.

  Status Function       Value      Description
                        Returned

 DXML_SUCCESS()        0          Succesful execution

 DXML_MAND_ARG()       1          Mandatory argument is missing

 DXML_ILL_WIGGLES()    5          wiggles is out of range

 DXML_ILL_FLOW()       6          flow is equal to fhigh

 DXML_ILL_F_RANGE()    7          flow or fhigh is out of range

 DXML_ILL_N_RANGE()    8          n is out of range

 DXML_ILL_N_NONREC()   9          n is less than (2*nterms+1)

 DXML_ILL_NTERMS()     10         nterms is out of range

Description

  The SFILTER_NONREC subroutine performs nonrecursive filtering in either
  lowpass, highpass, bandpass, or bandstop (notch) mode.  See
  the CXML Reference Guide  for information on controlling the filter type
  with the flow and fhigh arguments.