one time correlation experimental data fitted with ISF equation

[sameera2004]

No description provided.

[sameera2004]

@tacaswell I rebased this branch , test are not passing because some lines are not covered (coverage issue)

[sameera2004]

http://nbviewer.ipython.org/github/sameera2004/my_ipy_notebook/blob/master/Time_Correlation/ISF_fitting_repeat.ipynb

Ready for review

[tacaswell]

Needs to be

Notes
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[sameera2004]

Ipython notebook for one time correlation experimental data fitted with ISF equation

http://nbviewer.ipython.org/github/sameera2004/my_ipy_notebook/blob/master/Time_Correlation/XPCS_ISF_fitting_using_lmfit_model.ipynb

[sameera2004]

Thanks Tom

[licode]

Is lmfit used in correlation.py? I didn't find it implemented yet, maybe in a new PR?

[sameera2004]

@licode Not implemented, users can use lmfit to fit the experimental data with the intermediate scattering factor(ISF) equation. In the ipython notebook I showed it as an example.

Before I used to put residual functions using lmfit to get the experiment data and the model. using parameter class, (http://lmfit.github.io/lmfit-py/parameters.html).
After discussing with @danielballan, I took out those functions and only keep the model. (http://lmfit.github.io/lmfit-py/model.html#the-model-class)

@licode Therefore, following line in the correlation.py can be removed,
from lmfit import minimize, Model, Parameters

[licode]

I see. Because in the first ipython notebook example, corr.fit_auto_corr was implemented as a fitting function in correlation.py, but I couldn't find that function.

[sameera2004]

@licode yes I took that out, we don't need it anymore

[ericdill]

Can you put in a PR against scikit-xray-examples with that ipython notebook?

[sameera2004]

@ericdill sure I will

[licode]

It is better to define that function in ipython notebook if you took it out from source code, so users can understand which function is used for fitting. If that function is standard in the field, I suggest to include it in lineshapes.py.