MATLAB Compiler    
reallog

Natural logarithm for nonnegative real inputs.

Syntax

Description

reallog is an elementary function that operates element-wise on matrices. reallog returns the natural logarithm of X. The domain of reallog is the set of all nonnegative real numbers. If X is negative or complex, reallog issues an error message.

reallog is similar to the MATLAB log function; however, the domain of log is much broader than the domain of reallog. The domain of log includes all real and all complex numbers. If Y is real, you should use reallog rather than log for two reasons.

First, subsequent access of Y may execute more efficiently if Y is calculated with reallog rather than with log. Using reallog forces the MATLAB Compiler to impute a real type to X and Y. Using log typically forces the MATLAB Compiler to impute a complex type to Y.

Second, the compiled version of reallog may run somewhat faster than the compiled version of log. (However, the interpreted version of reallog may run somewhat slower than the interpreted version of log.)

See Also

exp, log, log2, logm, log10, realpow, realsqrt


 mbvector realpow