`LOG`

— Natural logarithm function ¶*Description*:`LOG(X)`

computes the natural logarithm of`X`, i.e. the logarithm to the base*e*.*Standard*:Fortran 77 and later, has GNU extensions

*Class*:Elemental function

*Syntax*:`RESULT = LOG(X)`

*Arguments*:`X`The type shall be `REAL`

or`COMPLEX`

.*Return value*:The return value is of type

`REAL`

or`COMPLEX`

. The kind type parameter is the same as`X`. If`X`is`COMPLEX`

, the imaginary part*\omega*is in the range*-\pi < \omega \leq \pi*.*Example*:program test_log real(8) :: x = 2.7182818284590451_8 complex :: z = (1.0, 2.0) x = log(x) ! will yield (approximately) 1 z = log(z) end program test_log

*Specific names*:Name Argument Return type Standard `ALOG(X)`

`REAL(4) X`

`REAL(4)`

Fortran 77 or later `DLOG(X)`

`REAL(8) X`

`REAL(8)`

Fortran 77 or later `CLOG(X)`

`COMPLEX(4) X`

`COMPLEX(4)`

Fortran 77 or later `ZLOG(X)`

`COMPLEX(8) X`

`COMPLEX(8)`

GNU extension `CDLOG(X)`

`COMPLEX(8) X`

`COMPLEX(8)`

GNU extension