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From: mike on 3 Jun 2010 05:39
I sometimes import data sets, generate theoretical curves based on
some expressions and then plot chi-square plots over a fairly large
parameter space. The way I had been doing this was using a dynamic
file browser and then something along the lines of the following
***some type of grid or nice frame***,
{FileNameSetter[Dynamic[f]], Dynamic[f], s = Take[Import[f, "Table"],
All, 2];}

(*s is the dataset*, I then pick a range of data I would like to see
fit and assign it to a new variable dat1. I choose a subset of the
range of values I am interested in fitting by bracketing the x axis
and extracting the {x,y} pairs*)

dat1={q1 = #[[1]] & /@ Select[s, x <= #[[1]] <= y &], inten = #[[2]]
& /@ Select[s, x <= #[[1]] <= y &]};

(*so the x, and y points I want are now labeled q1,and inten. the list
pair is given by dat1.*)

(*I now take the model and find the theoretical values*)
t = Table[{w, l, ((w/2)^2*l*Pi* NIntegrate[(((Sin[(q1*l*Cos[\
[Theta]])/ 2])/((q1*l*Cos[\[Theta]])/2)*(2*
BesselJ[1, q1*(w/2)*Sin[\[Theta]]])/(q1*(w/2)*Sin[\
[Theta]]))^2)*Sin[\[Theta]], {\[Theta], 0,
Pi/2}]*0.0287462*o*(1 - o))}, {w, 3, 15}, {l,
10,30}];
(*w is a width, l a length, and o is a parameter I provide to the
input. To find the chi-square for each set of points I use:*)
chi1 = Table[Total[((inten - t[[i, j, All]][[3]])^2)], {i, 1,
Dimensions[t][[1]]}, {j, 1, Dimensions[t][[2]]}];
(*the thrid column of the table t is now set to chi, giving a list
that reads {w,l,chi-square value} for the entire set of data*)
t[All,All,3]=chi
(*This is then flattened and is ready for List contour plot*)
ss1=Flatten[t,1];
ListContourPlot[ss1, opts...]

I have been trying to get this worked into part of a larger routine
where a checkbox initiates the entire procedure.
If have tried DynamicModule, Manipulate, etc. However the step 'chi1'
always fails to sum the difference of between inten and t. I also
tried Plus@@chi1 with an extra index . I would like to be able to
control the parameters x,y which determine what range of data is
evaluated by using an inputfield strucure for parameters x,y,o.

What am I doing incorrectly,
thanks

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