C
C There are a total of 3 entries in the algebraic variable array.
C There are a total of 4 entries in each of the rate and state variable arrays.
C There are a total of 9 entries in the constant variable array.
C
C
C VOI is time in component environment (day).
C STATES(1) is x in component x (per_mm3).
C CONSTS(1) is lamda in component x (per_mm3_per_day).
C CONSTS(2) is d in component x (per_day).
C CONSTS(3) is beta in component kinetic_parameters (mm3_per_day).
C ALGBRC(1) is s in component kinetic_parameters (dimensionless).
C STATES(2) is y in component y (per_mm3).
C CONSTS(4) is a in component y (per_day).
C CONSTS(5) is p in component kinetic_parameters (mm3_per_day).
C STATES(3) is z in component z (per_mm3).
C ALGBRC(2) is log_y in component y (dimensionless).
C STATES(4) is w in component w (per_mm3).
C CONSTS(6) is b in component w (per_day).
C CONSTS(7) is c in component kinetic_parameters (mm3_mm3_per_day).
C CONSTS(8) is q in component kinetic_parameters (per_mm3).
C ALGBRC(3) is log_w in component w (dimensionless).
C CONSTS(9) is h in component z (per_day).
C RATES(1) is d/dt x in component x (per_mm3).
C RATES(2) is d/dt y in component y (per_mm3).
C RATES(4) is d/dt w in component w (per_mm3).
C RATES(3) is d/dt z in component z (per_mm3).
C
      SUBROUTINE initConsts(CONSTS, RATES, STATES)
      REAL CONSTS(*), RATES(*), STATES(*)
      STATES(1) = 10
      CONSTS(1) = 1
      CONSTS(2) = 0.1
      CONSTS(3) = 0.5
      STATES(2) = 0.1
      CONSTS(4) = 0.2
      CONSTS(5) = 1
      STATES(3) = 0
      STATES(4) = 0.001
      CONSTS(6) = 0.01
      CONSTS(7) = 0.1
      CONSTS(8) = 0.5
      CONSTS(9) = 0.1
      RETURN
      END
      SUBROUTINE computeRates(VOI, CONSTS,  RATES, STATES, ALGBRC)
      REAL VOI, CONSTS(*), RATES(*), STATES(*), ALGBRC(*)
      RATES(4) =  CONSTS(7)*STATES(1)*STATES(2)*STATES(4) - ( CONSTS(7)*CONSTS(8)*STATES(2)*STATES(4)+ CONSTS(6)*STATES(4))
      RATES(3) =  CONSTS(7)*CONSTS(8)*STATES(2)*STATES(4) -  CONSTS(9)*STATES(3)
      ALGBRC(1) = TERNRY(VOI.LE.15.0000, 1.00000, TERNRY(VOI.GE.40.0000, 1.00000, 0.00420000)
      RATES(1) = CONSTS(1) - ( CONSTS(2)*STATES(1)+ ALGBRC(1)*CONSTS(3)*STATES(1)*STATES(2))
      RATES(2) =  ALGBRC(1)*CONSTS(3)*STATES(1)*STATES(2) - ( CONSTS(4)*STATES(2)+ CONSTS(5)*STATES(2)*STATES(3))
      RETURN
      END
      SUBROUTINE computeVariables(VOI, CONSTS, RATES, STATES, ALGBRC)
      REAL VOI, CONSTS(*), RATES(*), STATES(*), ALGBRC(*)
      ALGBRC(1) = TERNRY(VOI.LE.15.0000, 1.00000, TERNRY(VOI.GE.40.0000, 1.00000, 0.00420000)
      ALGBRC(2) = arbitrary_log( STATES(2)*1.00000, 10)
      ALGBRC(3) = arbitrary_log( STATES(4)*1.00000, 10)
      RETURN
      END
      REAL FUNCTION TERNRY(TEST, VALA, VALB)
      LOGICAL TEST
      REAL VALA, VALB
      IF (TEST) THEN
        TERNRY = VALA
      ELSE
        TERNRY = VALB
      ENDIF
      RETURN
      END