pro fgs,x,a,f
a=[0.,0.,0.,0.,0.,0.5]
n=256
x1=indgen(n)#replicate(1.,n)
y1=replicate(1.,n)#indgen(n)
x1=(x1-n/2)*(4./n)/pm
y1=(y1-n/2)*(4./n)/pm
r=sqrt(x1^2+y1^2)
t=atan(y1,x1)
tx =1.8992573*r*cos(t)
ty =1.8992573*r*sin(t)
fo =3.8874443*(r^2-0.554450)
ax =2.3137662*r^2*cos(2*t)
ay =2.3137662*r^2*sin(2*t)     
cx =8.3345629*(r^3-0.673796*r)*cos(t)
cy =8.3345629*(r^3-0.673796*r)*sin(t)
clx=2.6701691*r^3*cos(3*t)
cly=2.6701691*r^3*sin(3*t)
sa =16.895979*(r^4-1.108900*r^2+0.241243)                  
sax=12.033645*(r^4-0.750864*r^2)*cos(2*t)
say=12.033645*(r^4-0.750864*r^2)*sin(2*t)
ashx=29.851527*r^4*cos(4*t)
ashy=29.851527*r^4*sin(4*t)
prthru=cos(x1*1200.*2*!pi/(4.*25.4))*cos(y1*1200.*2*!pi/(4.*25.4))
i=complex(0.,1.)
wave=a(0)*fo+a(1)*cx+a(2)*cy+a(3)*ax+a(4)*ay+a(5)*sa
pupil=(r lt 1.) and (r gt 0.33) 
;;         pupil(where((abs(x1) lt 0.011) or (abs(y1) lt 0.011)))=0.
;         pupil(where((shift(r,0.0,0.889*n*pm/4) lt 0.063) or $
;                     (shift(r,0.826*n*pm/4,-0.340*n*pm/4) lt 0.063) or $
;                     (shift(r,-0.762*n*pm/4,-0.467*n*pm/4) lt 0.063))) =0. 
a=fltarr(100)& b=a


for it=0,99 do begin
   wav=(wave+(it-99)*tx/50.+0.*ty)*pupil
   wat=
endfor   
stop
end