Language Reference

LOG(X)

Natural logarithm.

X

must be of type real or complex.

• If X is real, its value must be greater than zero.
• If X is complex, its value must not be zero.

Class

Elemental function

Result Type and Attributes

Same as X.

Result Value

• It has a value approximating log_eX.
• For complex arguments, LOG ((a,b)) approximates LOG (ABS((a,b))) + ATAN2((b,a)).

  If the argument type is complex, the result is the principal value of the imaginary part &omega. in the range -&pi. < &omega. <= &pi.. If the real part of the argument is less than zero and its imaginary part is zero, the imaginary part of the result approximates &pi..

Examples

LOG (10.0) has the value 2.3025851 (approximately).

Notes:

1. IBM Extension: the ability to pass the name as an argument.