| Description: | Returns the natural logarithm of the argument. | ||
| Class: | Elemental function; Generic | ||
| Arguments: | 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. | ||
| Results: | The result type is the same as X. The result value is approximately equal to logeX. | ||
| If the arguments are complex, the result is the principal value of imaginary part omega in the range -pi < omega <= pi. The imaginary part of the result is pi if the real part of the argument is less than zero and the imaginary part of the argument is zero. | |||
| Specific Name | Argument Type | Result Type |
|---|---|---|
| ALOG 1 | REAL(4) | REAL(4) |
| DLOG | REAL(8) | REAL(8) |
| QLOG | REAL(16) | REAL(16) |
| CLOG 1 | COMPLEX(4) | COMPLEX(4) |
| CDLOG 2 | COMPLEX(8) | COMPLEX(8) |
| CQLOG | COMPLEX(16) | COMPLEX(16) |
|
1 The setting of compiler options specifying
real size can affect ALOG and CLOG.
2 This function can also be specified as ZLOG. | ||
Examples
LOG (8.0) has the value 2.079442.
LOG (25.0) has the value 3.218876.