run time error m6201 math log domain error

[shuddle]

hi all,

please help me to fix the above error.

C**********************************************************************************

FUNCTION HP(T)

C**********************************************************************************

REAL KA,KP,KR,MC,MH,MO,NA,N,NADNAX,NMO,NP,NPO,NX,KRR

COMMON/CHEM/KA,KP,KR,N(5),NA,NADNAX,NMO,NP,NPO,NX,RMR,KRR,

# MC,MH,MO,R,RLITAT,RMIX,Y,YCC,YMIN,PMOLWT

COMMON/CPCOEF/CV,ACPF,BCPF,ACPA,BCPA,AL(5),AH(5),

# BL(5),BH(5),CL(5),CH(5)

HP=0.

IF(T.GT.1600.0) GO TO 20

DO 1 I=1,5

1 HP=HP+N(I)*(AL(I)+BL(I)*T+CL(I)*ALOG(T))

RETURN

20 DO 3 I=1,5

3 HP=HP+N(I)*(AH(I)+BH(I)*T+CH(I)*ALOG(T))

RETURN

END

[TimP]

As you haven't done anything here to take care of negative values of T, it seems likely those would produce the reported diagnostic.