C INTLIN    SOURCE    CHAT      05/01/13    00:41:24     5004           
      SUBROUTINE INTLIN(TEMPS,KTE,KFT,LON,L1,L2, FT0,IRET)                      
      IMPLICIT INTEGER(I-N)
      IMPLICIT REAL*8(A-H,O-Z)                                                  
*--------------------------------------------------------------------*          
*                                                                    *          
*     INTERPOLATION LINEAIRE D'UNE VALEUR                            *          
*                                                                    *          
*     Param}tres:                                                    *          
*                                                                    *          
*  e  TEMPS   Abscisse @ interpoler                                  *          
*  e  KTE     LISTREEL des abscisses                                 *          
*  e  KFT     LISTREEL des ordonn{es                                 *          
*  e  LON     Longueur de la LISTREEL des abscisses                  *          
*  s  FT0     Valeur interpol{e                                      *          
*  s  IRET    IRET = 1, succ{s                                       *          
*  s  IRET    IRET = 0, {chec                                        *          
*                                                                    *          
*--------------------------------------------------------------------*          
-INC SMLREEL                                                                    
      FT0 = 0.D0                                                                
      MLREE1 = KTE                                                              
      MLREE2 = KFT                                                              
      T1 = MLREE1.PROG(L1)                                                      
      TL = MLREE1.PROG(LON)                                                     
      IF (TEMPS.LT.T1 .OR. TEMPS.GT.TL) THEN                                    
*        temps en dehors de la liste                                            
         IRET = 0                                                               
         RETURN                                                                 
      ENDIF                                                                     
      DO 10 L = L2,LON                                                          
         T2 = MLREE1.PROG(L)                                                    
         L2 = L                                                                 
         IF (TEMPS.LT.T2) GOTO 20                                               
         T1 = T2                                                                
         L1 = L2                                                                
 10      CONTINUE                                                               
*     end do                                                                    
 20   FT1 = MLREE2.PROG(L1)                                                     
      FT2 = MLREE2.PROG(L2)                                                     
      DT = (TEMPS - T1) / (T2 - T1)                                             
      FT0 = (FT2 - FT1) * DT + FT1                                              
      IRET = 1                                                                  
*                                                                               
      END