 
      COMPLEX FUNCTION CASIN(ZINP)
C***BEGIN PROLOGUE  CASIN
C***DATE WRITTEN   770701   (YYMMDD)
C***REVISION DATE  820801   (YYMMDD)
C***CATEGORY NO.  C4A
C***KEYWORDS  ARC SINE,COMPLEX,ELEMENTARY FUNCTION
C***AUTHOR  FULLERTON, W., (LANL)
C***PURPOSE  Computes the complex arc Sine.
C***DESCRIPTION
C
C CASIN(ZINP) calculates the complex trigonometric arc sine of ZINP.
C The result is in units of radians, and the real part is in the first
C or fourth quadrant.
C***REFERENCES  (NONE)
C***ROUTINES CALLED  R1MACH
C***END PROLOGUE  CASIN
 
 
