CRE Programmer's Guide

Math Functions
Common Run-Time Environment (CRE) Programmer’s Guide—528146-004
7-8
Exp
Exp
The Exp functions return e—the natural logarithm base—raised to the power passed
as a parameter to Exp.
number
is the exponent to which e is raised.
Return Value
The Exp functions return
e
number
where e is the natural logarithm base, approximately 2.718281828459045.
Considerations
An arithmetic fault occurs if an intermediate calculation causes an overflow or
underflow.
Ln
The Ln functions return a natural—that is, base e—logarithm.
number
is the number whose natural logarithm is returned.
Return Value
The Ln functions return “exponent,” where exponent satisfies the equation:
e
exponent
= number
REAL(32) PROC { CRE_Exp_Real32_ } ( number );
{ RTL_Exp_Real32_ }
REAL(32) number; ! in TNS only
REAL(64) PROC { CRE_Exp_Real64_ } ( number );
{ RTL_Exp_Real64_ }
REAL(64) number; ! in TNS only
REAL(32) PROC { CRE_Ln_Real32_ } ( number );
{ RTL_Ln_Real32_ }
REAL(32) number; ! in TNS only
REAL(64) PROC { CRE_Ln_Real64_ } ( number );
{ RTL_Ln_Real64_ }
REAL(64) number; ! in TNS only