C
C $Id: rdnext.F,v 1.2 1998/07/16 16:40:32 jjv5 Exp arjan $
C
C------------------------------------------------------------------------
      SUBROUTINE RDNEXT(STRING,ISTART,ISTOP,VALUE,IERROR)
C
C     SCANS A CHARACTER STRING FOR THE NEXT WORD, AND TRIES TO READ IN
C     THE WORD AS A DOUBLE PRECISION FLOATING POINT NUMBER.
C
C     INPUT
C     -----
C     STRING = CHARACTER STRING CONTAINING NUMBER.
C     ISTART = STARTING POINT OF SEARCH, I.E., STRING(ISTART:ISTART).
C
C     RETURNED
C     --------
C     ISTART = THE ACTUAL BEGINNING OF THE NUMERICAL FIELD.
C     ISTOP  = THE END OF THE NUMERICAL FIELD.
C     VALUE  = DOUBLE PRECISION NUMBER EXTRACTED FROM STRING(ISTART:ISTOP).
C     IERROR = ERROR CODE: 0 --> SUCCESSFUL READ
C                          1 --> ERROR ENCOUNTERED
C
      CHARACTER STRING*(*)
      DOUBLE PRECISION VALUE
      IERROR = 0
      CALL RDWORD(STRING,ISTART,ISTOP)
      IF(ISTART.EQ.0)THEN
        IERROR = 1
        GO TO 1000
      ENDIF
      CALL RDNUM(STRING,ISTART,VALUE,IERROR)
 1000 RETURN
      END