CERFE
This function evaluates a scaled function related to ERFC.
Function Return Value
CERFE — Complex function value. (Output)
Required Arguments
Z — Complex argument for which the function value is desired. (Input)
FORTRAN 90 Interface
Generic: CERFE (Z)
Specific: The specific interface names are C_CERFE and Z_CERFE.
FORTRAN 77 Interface
Complex: CERFE (Z)
Double complex:The double complex function name is ZERFE.
Description
Function CERFE is defined to be
Let b = AMACH(2) be the largest floating‑point number. The argument z must satisfy
or else the value returned is zero. If the argument z does not satisfy (ℑz)2‑(ℜz)2≤ log b, then b is returned. All other arguments are legal (Gautschi 1969, 1970).
Example
In this example, CERFE(2.5 + 2.5i) is computed and printed.
USE CERFE_INT
USE UMACH_INT
IMPLICIT NONE
! Declare variables
INTEGER NOUT
COMPLEX VALUE, Z
! Compute
Z = (2.5, 2.5)
VALUE = CERFE(Z)
! Print the results
CALL UMACH (2, NOUT)
WRITE (NOUT,99999) Z, VALUE
99999 FORMAT (' CERFE(', F6.3, ',', F6.3, ') = (', &
F6.3, ',', F6.3, ')')
END
Output
CERFE( 2.500, 2.500) = ( 0.117, 0.108)
