;+ 
; NAME:
;   oclc_fwd_y
;
; PURPOSE:
;   Calculates the flux.
;
; DESCRIPTION:
;
; CALLING SEQUENCE:
;   y = oclc_fwd_y(r, theta, distobs) 
;
; INPUTS: 
;  **** All inputs in cgs units ********
;
;  r - An array of radius values from the center of the planet, in cm.
;  theta - An bending angle in radians.
;  distobs - the distance to the observer, in cm.
;
; OUTPUTS:
;   
;  y - shadow radius (cm)
;
; COMMENTS:
;
; EXAMPLE 1 - scalar temperature, molecular weight
;   r = dindgen(400)*1d5 + 1200d5  ; array of r, in cm
;   km = 1e5
;   distobs = 30.*1.496e8*1.d5 ; 30 AU in cm
;   r0 = 1250d5 ; reference r in cm
;   nu0 = 2d-9
;   lam0 = 60.d
;   a = 0.d
;   b = 0.d
;   order = 4
;   dnu = oclc_ey92_dnu(r0,nu0,lam0,a,b, r)
;   theta = oclc_fwd_theta(r, dnu)
;   y = oclc_fwd_y(r, theta, distobs)
;   y2 = oclc_ey92_rho_of_r(r0,nu0,lam0,a,b, distobs, order, r)
;   
;   plot, r/1e5, (y-y2) / km
;   print, minmax( y-y2 ) / km ;
;
;   REVISON HISTORY:
;   25-Aug-2006 CBO SwRI -- modified from LAY's lightcurve.pro
;   19-Sep-2006 LAY SwRI.  Change _for_ to _fwd_, dist to distobs
;- 
function oclc_fwd_y, r, theta, distobs

    return,  r + theta * distobs

end