clog
, clogf
, clogl
Retrieves the natural logarithm of a complex number, with a branch cut along the negative real axis.
Syntax
_Dcomplex clog(
_Dcomplex z
);
_Fcomplex clog(
_Fcomplex z
); // C++ only
_Lcomplex clog(
_Lcomplex z
); // C++ only
_Fcomplex clogf(
_Fcomplex z
);
_Lcomplex clogl(
_Lcomplex z
);
Parameters
z
The base of the logarithm.
Return value
The natural logarithm of z
. The result is unbounded along the real axis and in the interval [-iπ, +iπ] along the imaginary axis.
The possible return values are:
z parameter |
Return value |
---|---|
Positive | The logarithm (base 10) of z |
Zero | - INF |
Negative | NaN |
NaN | NaN |
+ INF | + INF |
Remarks
Because C++ allows overloading, you can call overloads of clog
that take and return _Fcomplex
and _Lcomplex
values. In a C program, clog
always takes and returns a _Dcomplex
value.
Requirements
Routine | C header | C++ header |
---|---|---|
clog , clogf , clogl |
<complex.h> | <ccomplex> |
For more compatibility information, see Compatibility.
See also
Alphabetical function reference
cexp
, cexpf
, cexpl
cpow
, cpowf
, cpowl
clog10
, clog10f
, clog10l