FUNCTION lup_to_flux, lup, lup_err, b_soft

; Description: This function is called by the module "plot_light_motion_curve.pro".
;
; Author: Dan Bramich (dan.bramich@hotmail.co.uk)
;
; Dependencies: None
;
; History:
;
;   21/05/2013 - Module created (dmb).


;Convert luptitiude to flux
value = (-0.4D*alog(10.0D)*lup) - alog(b_soft)
flux = 2.0D*b_soft*sinh(value)
flux_err = abs(-0.8D*b_soft*alog(10.0D)*cosh(value))*lup_err

;Return the flux and its error
return, [flux, flux_err]

END