subroutine proc_f_on_rec (crec,iuins,iun,w,nyo,n,t,dt,v)

 Reads a time series from a file (unit IUN) and processes it with a filter.
  Takes parameters that control the reading from string CREC.
 Optionally reads filter control instruction string from file unit IUINS.
  Processes time series with the filter.

File input is carried out with a call to  read_fuf  in order to switch to one of three input types,
Bruxelles, Binary, Read_Fm_D.

Read_Fm_D  reads ASCII-files with a variety of date formats; from each record one time record
and one ordinate is read.  Read_Fm_D   is in  ~/sas/p/readfmd.f.

Binary data is read with  getts; routines are enclosed in  ~/sas/p/ufios.f

         Calling parameters

 CREC    - char**  - Command line; replaced by filter line on return
 IUINS   - integer - log.unit for filter control parameters
 IUN     - integer - log.unit, returned
 W(nyo)  - real*8  - Data array, returned, original dimension NYO
 N       - integer - Length, returned
 T,DT    - real*8
 V       - real*8  - c.f. below, returned to calling program

           Command line processing:

  iun,'trg',rec_mrs,'(fmt[)opt]',khms,itz,lldf,vp [,dtr] [T0=value] [-DC] [AMP=value]

The seven parameters to the left on the command lines are read with free format; therefore, commas are needed, and strings must be given with enclosing quotes.

Depending on the value of  lddf, Proc_F_On_Rec may continue to read from IUINS additional parameters (usually filter coefficients).

 iun     - integer - file unit for time-series input
  trg     - char*32 - target string for file positioning (read_fm_d only)
                     Special codes 'BIN' | 'BRX'  to read  binary  or  Bruxelles files.
                     Default mode is to call read_fm_d .
  rec_mrs - real*8  - missing record symbol

  fmt]opt - char*64 - format and option string | 'U' case 'BIN'ary files

                     In the case of 'BIN'ary files, segments from
                     multi-component files can be extracted by specifying the
                     label code here:

                     Unlabeled file: 'U'
Labeled file:   'L:label'

                     ASCII files: If a format string is given it must be enclosed
                     in parenthesis. After the closing parenthesis additional
                     options can be entered (delimiter = `, )
                     The following are processed by

                  DBG+  Debug mode on (excessive print)
                    P-  Print mode off (very little will be printed)
                   T+ Add x [hours] to the file time.

                    The following options are processed by
                     read_fuf (ufios.f); some of them can be passed through the
                     TRG string

                   Rwd  rewind the file before processing.                  TRG FMT
                   Y:Floating point date records are decimal years.
                         Fix at specified year, Jan 1 (Read_FM_D only).     TRG FMT
                   J:D  Long Julian Day (incl.base 2400000)
                J[D]:O  RJD, Official definition of Julian date (new day
                         starts at noon), D for Long Julian Day
                J[D]:I  MJD, new day starts at midnight (default J:I)           FMT
                   J+ Floating-point days. Record is interpreted as
                        days after Julian day v. If no epoch is defined
                        yet, it will be set at v.                               FMT
                  Fh: fix origin time at this hour.                       TRG FMT
                  Dm: Doubt-margin for read_fm_doubt (value)                  FMT
               DF:code  Date format code; avoid parenthesis  ['I2,I4,I3']       FMT
                   M>0  Convert MRS's to zero                                   FMT
              DH+[h,s]  Time record is date and a floating point number t.
                        Compute hour as h + t s.
[h,s]  ... compute hour as h + t/s. Default h=0, s=1           FMT
                   T+ Add x [hours] to the file time.                         FMT
               Y2K[:y]  Convert for Year 2000. Years less than y are
                        assumed to be after 2000,
                        those between y and 100 before 2000.                    FMT

                                                Some errors that are encountered trigger a counting
                        meachanism. In cases of doubt, invoke tslist with
                        the -DBG option. The input loop can be escaped using
                        the error-count option
                ,#E=n   This will allow n errors at maximum
                ,#E=0   will print extra information at errors
                ,#E=-1  will permit infinitely many errors

                     The format string will be analyzed by read_fm_d
                     to find out the kind of time-record format. Four cases
                     are distinguished:

              (1)    A leading floating point number indicates Julian dates.
              (2)    If decimal years are to be input, Y:fixyear must be given.
              (3)    If a string precedes numeric input, read_fm_d assumes that
                     month is coded as a 3-char string. A special conversion
                     routine is called that reformats month prose into integer in-place.
                     The DF:code option is used to specify this intermediate format.
                     Therefore if a record is given as
                             1998-AUG-25 123.456
                     it must be read with
                            FMT='(A11,F8.3) DF:I4,1X,I3,1X,I2'
              (4)    Else the system expects integer Year Month Day [Hour [Minute [Second]]]
                     Then, FMT must contain KHMS+3 integer fields in front of the
                     format for the ordinate value.

 khms    - integer - time record "depth": read hours, minutes and seconds (0..3)
                     Applies to integer records (DH+ option inactive)

 itz     - integer - time zone (+1 for CET)

 lddf    - integer -
                     0 or -2: Process with scaling.
                              The command line following contains the scale factor.

                              Optionally, the scale factor may be used for
                              converting air pressure into input-data units;
                              this is effectuated if the line contains "PCAL".
                              Recommended if air pressure results will be
                              combined into the present solution. Only inside urtap though!
                    -1 or -3: No scaling. No command line follows.
                    -2 or -3: Subtract DC-level. No command line follows.
                          -9: Scale factor from AMP=value option, default=1 No command line follows.
                    lddf > 0: Next command line describes filter:
                              Scale factor, NFM,NFP,SYMM.
                              Follow: NFP-NFM+1 filter coefficients.

 vp      - real*8  - constant. Needed e.g. for '+' (LINCOMB) processing (the value is simply returned
                     through the call list of proc_f_on_rec and the calling program decides what to
                     do with it). 

                     Default = -1.
 [dtr]   - real*8  - optional: sampling interval. If not given, dt from
                     the call list is used. Specify 0.0 to let the read
                     routine detect it.

 T0=value  option  - Impose value for t0 on the call to the read routine.
                     May be useful to resynch the times.
                     To be coded without blanks.
 -DC       option  - Remove DC-level
  AMP=value option  - together with LDDF=-9. value is
                     either a numeric value or a name (char*16).
                     In the latter case, the names and associated values
                     must be passed to this routine via common blocks
                      /CPRFOR/ N, VALUES
                      /CCPRFO/ NAMES
                     Program urtap assigns variables named PTX and PTY (pole tide
                     amplitudes). They can be set through namelist.
                     If you want to scale the time-series that is described here with
                     that PTX value, add AMP=PTX at the end of the command line.
                     (i.e. to scale the IERS EOP X series). And likewise for Y.

Examples badly needed! Check with *.tse files and urtap.ins #-instructions.