CTITLESARICK -- RICKER WAVELET CALCULATION                              00000010
C***********************************************************************
C                 COPYRIGHT ATLANTIC RICHFIELD COMPANY 1991            *
C***********************************************************************
CA    AUTHOR               D. NYMAN                                     00000020
CA    DESIGNER             D. NYMAN                                     00000030
CA    LANGUAGE             S/370 FORTRAN H                              00000040
CA    WRITTEN              06/07/78                                     00000050
C     REVISED                                                           00000060
C                                                                       00000070
CA                                                                      00000080
CA                                                                      00000090
CA    CALL SARICK (WO, PARM, NWO, SMPINT)                               00000100
CA         OUTPUT WO      = ARRAY OF RICKER WAVELET VALUES.         R4  00000110
CA         INPUT  PARM(1) = RICKER WAVELET FREQUENCY IN HZ.         I4  00000120
CA         OUTPUT NWO     = NUMBER OF VALUES IN WO.                 I4  00000130
CA         INPUT  SMPINT  = SAMPLING INTERVAL IN MS.                I4  00000140
CA                                                                      00000150
CA                                                                      00000160
CA    THIS ROUTINE CALCULATES A RICKER WAVELET OF THE FREQUENCY         00000170
CA    GIVEN IN PARM(1).  ALL TERMS OF ABSOLUTE VALUE GREATER THAN       00000180
CA    SOME PRE-DETERMINED VALUE (RELATED TO BLIM) ARE RETURNED.         00000190
CA                                                                      00000200
C=======================================================================00000210
C     EJECT                                                             00000220
C=======================================================================00000230
C                                                                       00000240
C     CONSTANTS AND VARIABLES -- LOCAL                                  00000250
C                                                                       00000260
C        BLIM = CUTOFF PARAMETER                                    R4  00000270
C         LWH = CENTER (TIME = 0) INDEX                             I4  00000280
C          PI = VALUE OF PI (3.14159....)                           R4  00000290
C                                                                       00000300
C=======================================================================00000310
C     EJECT                                                             00000320
C                                                                       00000330
      SUBROUTINE SARICK (WO, PARM, NWO, SMPINT)                         00000340
C                                                                       00000350
      INTEGER PARM,SMPINT                                               00000360
      DIMENSION WO(1),PARM(1)                                           00000370
      DATA PI /3.14159265/, BLIM /3.4/                                  00000380
C                                                                       00000390
C                 INITIALIZE VALUES                                     00000400
C                                                                       00000410
      PIFDT=PI*PARM(1)*SMPINT*.001                                      00000420
      LWH=BLIM/PIFDT+1.5                                                00000430
      NWO=2*LWH-1                                                       00000440
      WO(LWH)=1.                                                        00000450
      K=LWH-1                                                           00000460
C                                                                       00000470
C                 CALCULATE WAVELET                                     00000480
C                                                                       00000490
      DO 10 I=1,K                                                       00000500
      B=PIFDT*I                                                         00000510
      BB=B*B                                                            00000520
      WI=(1.0-2.0*BB)*EXP(-BB)                                          00000530
      WO(LWH+I)=WI                                                      00000540
   10 WO(LWH-I)=WI                                                      00000550
C                                                                       00000560
      RETURN                                                            00000570
C                                                                       00000580
      END                                                               00000590