C 
C Program SRP (Source and Receiver Points, or SuRface Points) to
C generate files containing source and/or receiver points corresponding
C to given configuration parameter(s).
C
C The dependence of the source and receiver coordinates on the
C configuration parameters is assumed to be linear.
C
C Version: 5.50
C Date: 2001, May 10
C
C Coded by: Ludek Klimes
C     Department of Geophysics, Charles University Prague,
C     Ke Karlovu 3, 121 16 Praha 2, Czech Republic,
C     E-mail: klimes@seis.karlov.mff.cuni.cz
C
C.......................................................................
C                                                    
C Description of data files:
C
C Input data read from the standard input device (*):
C     The data are read by the list directed input (free format) and
C     consist of a single string 'SEP':
C     'SEP'...String in apostrophes containing the name of the input
C             SEP parameter or history file with the input data.
C     No default, 'SEP' must be specified and cannot be blank.
C
C                                                     
C Input data file 'SEP':
C     File 'SEP' has the form of the SEP
C     parameter file.  The parameters, which do not differ from their
C     defaults, need not be specified in file 'SEP'.
C Name of the input file, configuration parameters:
C     SRP='string'...Name of the input file specifying the unshifted
C             points corresponding to zero configuration parameters,
C             and the derivatives of their positions with respect to the
C             configuration parameters.
C             Description of the file SRP
C             Default: 'SRP'='srp.dat'
C     CNAME='string'... Character string which is, without trailing
C             blanks, prefixed to the name of each unshifted point in
C             order to create the name of the corresponding point
C             shifted according to the configuration parameters CPAR1,
C             CPAR2.
C             Default: 'CNAME'=' '
C     CPAR1=real, CPAR2=real...Configuration parameters describing new,
C             shifted positions of the given surface points.
C             Default: CPAR1=0., CPAR2=0.
C Optional parameters specifying the form of the real quantities
C written in the output formatted files:
C     MINDIG,MAXDIG=positive integers ... See the description in file
C             forms.for.
C
C                                                     
C Input file 'SRP' with the unshifted points:
C (1) 'PTS1','PTS2','PTS3',...,/
C     One to MFILE=1024 filenames terminated by a slash.  Names of the
C     output files with the shifted surface points, corresponding to
C     given configuration parameters CPAR1, CPAR2.  It is thus assumed,
C     that the shifted points are written to the same files for all
C     values of the configuration parameters.  A filename should not
C     exceed 12 characters.
C (2) For each filename, data (2.1) and (2.2):
C (2.1) For each point to be written to the output file data (2.1.1):
C (2.1.1) 'NAME',X10,X20,X30,X11,X21,X31,X12,X22,X32,/
C     'NAME'..Name of the unshifted point.  It will be appended to given
C             string 'CNAME' (with trailing blanks removed from both
C             'CNAME' and 'NAME') to form the name of the corresponding
C             shifted point.  The resulting composed name 'CNAMENAME' is
C             truncated to 80 characters.  However, some other
C             applications may truncate the names of points to 12, 11,
C             8, or even 6 characters.
C      X10,X20,X30... Coordinates of the unshifted points.
C      X11,X21,X31... Derivatives of the coordinates with respect to the
C             first configuration parameter CPAR1.
C      X12,X22,X32... Derivatives of the coordinates with respect to the
C             second configuration parameter CPAR2.
C      Default: X10=0., X20=0., X30=0., X11=0., X21=0., X31=0., X12=0.,
C             X22=0., X32=0.
C (2.2) /
C
C                                                     
C Output files PTS with the shifted surface points:
C (1) /
C (2) For each shifted point data (2.1):
C (2.1) 'CNAMENAME',X1,X2,X3,/
C     'CNAMENAME'..Name of the shifted point.
C      X1,X2,X3... Coordinates of the shifted point,
C                  X1=X10+X11*CPAR1+X12*CPAR2,
C                  X2=X20+X21*CPAR1+X22*CPAR2,
C                  X3=X30+X31*CPAR1+X32*CPAR2.
C (3) /
C
C-----------------------------------------------------------------------
C
      CHARACTER*80 FILSEP
      INTEGER LU
      PARAMETER (LU=1)
C
C     Filenames:
      INTEGER MFILE
      PARAMETER (MFILE=1024)
      CHARACTER*12 FILE1(MFILE)
      CHARACTER*80 FILE0
C
C     Logical unit numbers:
      INTEGER LU0,LU1
      PARAMETER (LU0=10)
      PARAMETER (LU1=11)
C
C     Data:
      CHARACTER*80 NAME
      CHARACTER*8 CNAME
      CHARACTER*28 FORMAT
      INTEGER I,J,L
      REAL X(3),X1,X2,X3,X10,X20,X30,X11,X21,X31,X12,X22,X32,C1,C2
      EQUIVALENCE (X(1),X1),(X(2),X2),(X(3),X3)
C
C     I,J...  Loop variables.
C     X1,X2,X3... Coordinates of a point.
C     X00,X10,X20,X01,X11,X21,X02,X12,X22... Projection matrix from
C             configuration parameters to coordinates of a point.
C     C1,C2.. Configuration parameters of a point.
C
C-----------------------------------------------------------------------
C
C     Reading name of SEP file with input data:
      WRITE(*,'(A)') '+SRP: Enter input filename: '
      FILSEP=' '
      READ(*,*) FILSEP
      WRITE(*,'(A)') '+SRP: Working ...           '
C
C     Reading all data from the SEP file into the memory:
      IF (FILSEP.NE.' ') THEN
        CALL RSEP1(LU,FILSEP)
      ELSE
C       SRP-01
        CALL ERROR('SRP-01: SEP file not given')
C       Input file in the form of the SEP (Stanford Exploration Project)
C       parameter or history file must be specified.
C       There is no default filename.
      ENDIF
C
C     Reading input parameters from the SEP file:
      CALL RSEP3T('SRP',FILE0,'srp.dat')
      CALL RSEP3T('CNAME',CNAME,' ')
      CALL RSEP3R('CPAR1',C1,0.)
      CALL RSEP3R('CPAR2',C2,0.)
C
      OPEN(LU0,FILE=FILE0,STATUS='OLD')
      DO 10 I=1,MFILE
        FILE1(I)='$'
   10 CONTINUE
      READ(LU0,*) (FILE1(I),I=1,MFILE)
C
      DO 11 L=LEN(CNAME),1,-1
        IF(CNAME(L:L).NE.' ') THEN
          GO TO 12
        END IF
   11 CONTINUE
   12 CONTINUE
      L=L+1
C
C     Loop over output surface-point files:
      DO 30 I=1,MFILE
        IF(FILE1(I).EQ.'$') THEN
          GO TO 90
        END IF
        OPEN(LU1,FILE=FILE1(I))
        WRITE(LU1,'(A)') '/'
   20   CONTINUE
          NAME=CNAME
          NAME(L:L)='$'
          X10=0.
          X20=0.
          X30=0.
          X11=0.
          X21=0.
          X31=0.
          X12=0.
          X22=0.
          X32=0.
          READ(LU0,*) NAME(L:80),X10,X20,X30,X11,X21,X31,X12,X22,X32
          IF(NAME(L:80).EQ.'$'
     *                  .AND.X10.EQ.0..AND.X20.EQ.0..AND.X30.EQ.0.
     *                  .AND.X11.EQ.0..AND.X21.EQ.0..AND.X31.EQ.0.
     *                  .AND.X12.EQ.0..AND.X22.EQ.0..AND.X32.EQ.0.) THEN
            GO TO 29
          END IF
          DO 21 J=LEN(NAME),2,-1
            IF(NAME(J:J).NE.' ') THEN
              GO TO 22
            END IF
   21     CONTINUE
   22     CONTINUE
          X1=X10+X11*C1+X12*C2
          X2=X20+X21*C1+X22*C2
          X3=X30+X31*C1+X32*C2
          FORMAT(1:4)='(3A,'
          CALL FORM2(3,X,X,FORMAT(5:28))
          WRITE(LU1,FORMAT) '''',NAME(1:J),''' ',X1,' ',X2,' ',X3,' /'
        GO TO 20
   29   CONTINUE
        WRITE(LU1,'(A)') '/'
        CLOSE(LU1)
   30 CONTINUE
C
   90 CONTINUE
      CLOSE(LU0)
      WRITE(*,'(A)') '+SRP: Done.                 '
      STOP
      END
C
C=======================================================================
C
      INCLUDE 'error.for'
C     error.for
      INCLUDE 'sep.for'
C     sep.for
      INCLUDE 'forms.for'
C     forms.for
      INCLUDE 'length.for'
C     length.for
C
C=======================================================================
C