LOG10

This function extends FORTRAN’s generic log10 function to evaluate the principal value of the complex common logarithm.

Function Return Value

LOG10 — Complex function value. (Output)

Required Arguments

Z — Complex argument for which the function value is desired. (Input)

FORTRAN 90 Interface

Generic: LOG10 (Z)

Specific: The specific interface names are CLOG10 and ZLOG10.

FORTRAN 77 Interface

Complex: CLOG10 (Z)

Double complex: The double complex function name is ZLOG10.

Description

The function LOG10(Z) evaluates log10 (z) . The argument must not be zero, and ∣z∣ must not overflow.

Example

In this example, the log10(0.0076i) is computed and printed.

 

USE LOG10_INT

USE UMACH_INT

 

IMPLICIT NONE

! Declare variables

INTEGER NOUT

COMPLEX VALUE, Z

! Compute

Z = (0.0, 0.0076)

VALUE = LOG10(Z)

! Print the results

CALL UMACH (2, NOUT)

WRITE (NOUT,99999) Z, VALUE

99999 FORMAT (' LOG10((', F7.4, ',', F7.4, ')) = (', &

F6.3, ',', F6.3, ')')

END

Output

 

LOG10(( 0.0000, 0.0076)) = (-2.119, 0.682)