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subroutine ddpowe(v,p,rr,ri,ierr,iscmpl)
c!purpose
c computes v^p with p and v double precision
c!calling sequence
c subroutine ddpowe(v,p,rr,ri,ierr,iscmpl)
c integer ierr
c double precision v,p,rr,ri
c
c rr : result's real part
c ri : result's imaginary part
c ierr : error flag
c ierr=0 if ok
c ierr=1 if 0**0
c ierr=2 if 0**k with k<0
c iscmpl :
c iscmpl=0 if result is real
c iscmpl=1 if result is complex
c!origin
c Serge Steer INRIA 1996
c!
c Copyright INRIA
integer ierr
double precision v,p,sr,si,rr,ri,infinity
c
ierr=0
iscmpl=0
c
if(dble(int(p)).eq.p) then
call dipowe(v,int(p),rr,ierr)
ri=0.0d0
else
if(v.gt.0.0d+0) then
rr=v**p
ri=0.0d0
elseif(v.lt.0.0d+0) then
call wlog(v,0.0d0,sr,si)
sr=exp(sr*p)
si=si*p
rr=sr*cos(si)
ri=sr*sin(si)
iscmpl=1
elseif(v.eq.0.d0) then
if(p.lt.0.0d+0) then
ri=0.0d0
rr=infinity(ri)
ierr=2
elseif(p.eq.0.0d+0) then
c ierr=1
rr=1.0d0
ri=0.0d0
elseif(p.gt.0.d0) then
rr=0.0d0
ri=0.0d0
else
c p is nan
rr = p
ri = 0.d0
endif
else
c v is nan
rr = v
ri = 0.d0
endif
endif
c
return
end
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