pro encirc,a,ee,psf pix=0.043 nx=n_elements(a(*,0)) ny=n_elements(a(0,*)) x1=indgen(nx)#replicate(1.,ny) y1=replicate(1.,nx)#indgen(ny) maxa=where(a eq max(a)) &my=maxa(0)/nx &mx=maxa(0)-my*nx x1=(x1-mx)*pix y1=(y1-my)*pix r=sqrt(x1^2+y1^2) t=atan(y1,x1) EE=fltarr(nx/2) PSF=fltarr(nx/2) for i=0,n_elements(ee)-2 do begin valid=where((r gt i*pix) and (r lt (i+1)*pix)) If(n_elements(valid) ne 1) then begin psf(i)=total(a(valid))/n_elements(valid) ee(i+1)=ee(i)+total(a(valid)) endif else begin ee(i+1)=ee(i) endelse endfor stop end