LOG
Platform  x64, Win32, .NET 
Purpose 
To get the natural logarithm of the argument. 
Class 
Elemental function. 
Syntax 
REAL FUNCTION LOG(X); REAL X
COMPLEX FUNCTION LOG(X); COMPLEX X 
Description 
If X is real, its value must be greater than zero. If X is complex, its value
must not be zero. 
Return value 
The result has the value log e X. A complex
result is the principal value with imaginary part w in the range p
< w < p.
The imaginary part of the result is
p
only when the real part of the argument is less than zero and the imaginary
part of the argument is zero. 

