Subject: Re: [nmr_sparky] RH command
From: Thomas Goddard
Date: Mar 28, 2006

Previous: 93

Hi Tiago,

Fitting the decaying exponential A*exp(Bt) to peak heights uses a
gradient descent type of approach in the parameter space (A,B). The
fitting is done in Sparky Python code

sparky/python/sparky/curvefit.py

and it gives up after 100 steps. So it should never hang, even if
the minimization does not converge. Also I would not expect the steps
to take very long, although the step time is proportional to the
square of the number of spectra.

You could put a print statement in curvefit.py in the find_fit() function
right after the step_count is incremented to see the progress:

self.step_count = self.step_count + 1
print self.step_count

Youll need to have the Sparky Extensions/Python Shell window open to see
the output. And you could change the max_steps = 100 line so it gives
up after fewer steps if needed.

Tom