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