# ctan.f

          COMPLEX FUNCTION CTAN (Z)
    C***BEGIN PROLOGUE  CTAN
    C***PURPOSE  Compute the complex tangent.
    C***LIBRARY   SLATEC (FNLIB)
    C***CATEGORY  C4A
    C***TYPE      COMPLEX (CTAN-C)
    C***KEYWORDS  ELEMENTARY FUNCTIONS, FNLIB, TANGENT, TRIGONOMETRIC
    C***AUTHOR  Fullerton, W., (LANL)
    C***DESCRIPTION
    C
    C CTAN(Z) calculates the complex trigonometric tangent of complex
    C argument Z.  Z is in units of radians.
    C
    C***REFERENCES  (NONE)
    C***ROUTINES CALLED  R1MACH, XERCLR, XERMSG
    C***REVISION HISTORY  (YYMMDD)
    C   770401  DATE WRITTEN
    C   890531  Changed all specific intrinsics to generic.  (WRB)
    C   890531  REVISION DATE from Version 3.2
    C   891214  Prologue converted to Version 4.0 format.  (BAB)
    C   900315  CALLs to XERROR changed to CALLs to XERMSG.  (THJ)
    C***END PROLOGUE  CTAN