[ar,ai,br,bi,cr,ci]=zmlt(ar,ai,br,bi,cr,ci);

function [ar,ai,br,bi,cr,ci]=zmlt(ar,ai,br,bi,cr,ci);
%***BEGIN PROLOGUE  ZMLT
%***SUBSIDIARY
%***PURPOSE  Subsidiary to ZBESH, ZBESI, ZBESJ, ZBESK, ZBESY, ZAIRY and
%            ZBIRY
%***LIBRARY   SLATEC
%***TYPE      ALL (ZMLT-A)
%***AUTHOR  Amos, D. E., (SNL)
%***DESCRIPTION
%
%     doubleprecision COMPLEX MULTIPLY, C=A*B.
%
%***SEE ALSO  ZAIRY, ZBESH, ZBESI, ZBESJ, ZBESK, ZBESY, ZBIRY
%***ROUTINES CALLED  (NONE)
%***REVISION HISTORY  (YYMMDD)
%   830501  DATE WRITTEN
%   910415  Prologue converted to Version 4.0 format.  (BAB)
%***end PROLOGUE  ZMLT
persistent ca cb ; 

if isempty(ca), ca=0; end;
if isempty(cb), cb=0; end;
%***FIRST EXECUTABLE STATEMENT  ZMLT
ca = ar.*br - ai.*bi;
cb = ar.*bi + ai.*br;
cr = ca;
ci = cb;
end
%DECK ZRATI