1*DECK CARG
2      FUNCTION CARG (Z)
3C***BEGIN PROLOGUE  CARG
4C***PURPOSE  Compute the argument of a complex number.
5C***LIBRARY   SLATEC (FNLIB)
6C***CATEGORY  A4A
7C***TYPE      COMPLEX (CARG-C)
8C***KEYWORDS  ARGUMENT OF A COMPLEX NUMBER, ELEMENTARY FUNCTIONS, FNLIB
9C***AUTHOR  Fullerton, W., (LANL)
10C***DESCRIPTION
11C
12C CARG(Z) calculates the argument of the complex number Z.  Note
13C that CARG returns a real result.  If Z = X+iY, then CARG is ATAN(Y/X),
14C except when both X and Y are zero, in which case the result
15C will be zero.
16C
17C***REFERENCES  (NONE)
18C***ROUTINES CALLED  (NONE)
19C***REVISION HISTORY  (YYMMDD)
20C   770401  DATE WRITTEN
21C   861211  REVISION DATE from Version 3.2
22C   891214  Prologue converted to Version 4.0 format.  (BAB)
23C***END PROLOGUE  CARG
24      COMPLEX Z
25C***FIRST EXECUTABLE STATEMENT  CARG
26      CARG = 0.0
27      IF (REAL(Z).NE.0. .OR. AIMAG(Z).NE.0.) CARG =
28     1  ATAN2 (AIMAG(Z), REAL(Z))
29C
30      RETURN
31      END
32