C
C There are a total of 3 entries in the algebraic variable array.
C There are a total of 2 entries in each of the rate and state variable arrays.
C There are a total of 14 entries in the constant variable array.
C
C
C VOI is time in component environment (day).
C CONSTS(1) is s in component uninfected (per_day_mm3).
C CONSTS(2) is p in component uninfected (per_day).
C CONSTS(3) is gamma in component uninfected (per_day).
C CONSTS(14) is beta in component uninfected (dimensionless).
C CONSTS(4) is N in component free_virus_particle (dimensionless).
C CONSTS(5) is k_1 in component latently_infected (mm3_per_day).
C CONSTS(6) is k_2 in component actively_infected (per_day).
C CONSTS(7) is k_3 in component latently_infected (per_day).
C CONSTS(8) is mu_V in component free_virus_particle (per_day).
C STATES(1) is T_1 in component latently_infected (per_mm3).
C CONSTS(9) is mu_b in component actively_infected (per_day).
C STATES(2) is T in component uninfected (per_mm3).
C CONSTS(10) is k_4 in component latently_infected (per_day).
C CONSTS(11) is T_0 in component latently_infected (per_mm3).
C CONSTS(12) is V_0 in component latently_infected (per_mm3).
C CONSTS(13) is t_min in component latently_infected (day).
C ALGBRC(1) is T_1_t in component latently_infected (per_mm3).
C ALGBRC(2) is T_2 in component actively_infected (per_mm3).
C ALGBRC(3) is V in component free_virus_particle (per_mm3).
C RATES(2) is d/dt T in component uninfected (per_mm3).
C RATES(1) is d/dt T_1 in component latently_infected (per_mm3).
C
      SUBROUTINE initConsts(CONSTS, RATES, STATES)
      REAL CONSTS(*), RATES(*), STATES(*)
      CONSTS(1) = 10
      CONSTS(2) = 0.01
      CONSTS(3) = 2E-5
      CONSTS(4) = 1000
      CONSTS(5) = 2.4E-5
      CONSTS(6) = 3E-3
      CONSTS(7) = 0.023
      CONSTS(8) = 2.4
      STATES(1) = 0
      CONSTS(9) = 0.24
      STATES(2) = 1000
      CONSTS(10) = 2.424
      CONSTS(11) = 1000
      CONSTS(12) = 1E-3
      CONSTS(13) = 2
      CONSTS(14) =  (CONSTS(3)/CONSTS(7))*(1.00000+CONSTS(6)/CONSTS(9))
      RETURN
      END
      SUBROUTINE computeRates(VOI, CONSTS,  RATES, STATES, ALGBRC)
      REAL VOI, CONSTS(*), RATES(*), STATES(*), ALGBRC(*)
      RATES(2) = ((CONSTS(1)+ CONSTS(2)*STATES(2)) -  CONSTS(3)*STATES(2) ** 2.00000) -  ( CONSTS(7)*CONSTS(14)+( CONSTS(4)*CONSTS(5)*CONSTS(6))/( CONSTS(5)*STATES(2)+CONSTS(8)))*STATES(2)*STATES(1)
      ALGBRC(1) =  (( CONSTS(5)*CONSTS(11)*CONSTS(12))/(CONSTS(10) - CONSTS(7)))*(EXP( - CONSTS(7)*VOI) - EXP( - CONSTS(10)*VOI))
      RATES(1) = TERNRY(VOI.LE.CONSTS(13), ALGBRC(1),  (( CONSTS(4)*CONSTS(5)*CONSTS(6))/( CONSTS(5)*STATES(2)+CONSTS(8)))*STATES(2)*STATES(1) -  CONSTS(7)*STATES(1))
      RETURN
      END
      SUBROUTINE computeVariables(VOI, CONSTS, RATES, STATES, ALGBRC)
      REAL VOI, CONSTS(*), RATES(*), STATES(*), ALGBRC(*)
      ALGBRC(1) =  (( CONSTS(5)*CONSTS(11)*CONSTS(12))/(CONSTS(10) - CONSTS(7)))*(EXP( - CONSTS(7)*VOI) - EXP( - CONSTS(10)*VOI))
      ALGBRC(2) = ( CONSTS(6)*STATES(1))/CONSTS(9)
      ALGBRC(3) = ( CONSTS(4)*CONSTS(6)*STATES(1))/( CONSTS(5)*STATES(2)+CONSTS(8))
      RETURN
      END
      REAL FUNCTION TERNRY(TEST, VALA, VALB)
      LOGICAL TEST
      REAL VALA, VALB
      IF (TEST) THEN
        TERNRY = VALA
      ELSE
        TERNRY = VALB
      ENDIF
      RETURN
      END