PRO LINERECT,spectr,a,b,c,rectspe,x0
;
; Rectification of spectral curvature
; INPUT: SPECTR - 2D array with original spectrum
;        A, B, C - coefficients of the parabola
; OUTPUTS: RECTSPE - rectified spectrum
;          x0 - position of the line
;
; Copyright M. Klvana and M. Sobotka, ASU AVCR Ondrejov, Czech Rep., 2008
;

si=size(spectr)
y=findgen(si(2))
x=a+b*y+c*y^2       ;calculate curvature parabola
x0=x(si(2)/2)       ;set zero in the middle of FOV
shft=x-x0           ;array of curvature shifts
rectspe=float(spectr)

for j=0,si(2)-1 do begin

    xx=findgen(si(1))+shft(j)
    rect=interpolate(float(spectr(*,j)),xx)
    rectspe(*,j)=rect

endfor

END