'file to fit a simple Gaussian function

'this tells topas filename, how to weight data and how often to calculate data points
xdd gaussian.xy
weighting 1
x_calculation_step = Yobs_dx_at(Xo); 

'these lines define the constants and paramaters in our Gaussian equation
'! means fix the parameter
'the bkg @ 10 fits a linear background to the data
prm !c0 2.775289
prm !pi 3.14159
prm fwhm  0.30015`
prm intensity  104.99998`
prm pos  3.00000`

bkg @  10`

fit_obj = intensity * (c0^0.5/(fwhm*pi^0.5))*Exp( (-c0*(X-pos)^2)/fwhm^2  );

'do_errors