Re: [Numpy-discussion] Calculation of a hessian

2014-08-10 Thread Kiko
2014-08-08 16:37 GMT+02:00 Eelco Hoogendoorn : > Do it in pure numpy? How about copying the source of numdifftools? > Of course it is a solution. I was just wondering if it exist something similar in the numpy/scipy packages so I do not have to use a new third party library to do that. > What e

Re: [Numpy-discussion] Calculation of a hessian

2014-08-10 Thread Kiko
2014-08-08 11:51 GMT+02:00 Jose Gomez-Dans : > Your function looks fairly simple to differentiate by hand, but if you > have access to the gradient (or you estimate it numerically using > scipy...), this function might do the job: > > def hessian ( x, the_func, epsilon=1e-8): > """Numerical ap

Re: [Numpy-discussion] Calculation of a hessian

2014-08-08 Thread Eelco Hoogendoorn
Do it in pure numpy? How about copying the source of numdifftools? What exactly is the obstacle to using numdifftools? There seem to be no licensing issues. In my experience, its a crafty piece of work; and calculating a hessian correctly, accounting for all kinds of nasty floating point issues, i

Re: [Numpy-discussion] Calculation of a hessian

2014-08-08 Thread Jose Gomez-Dans
Your function looks fairly simple to differentiate by hand, but if you have access to the gradient (or you estimate it numerically using scipy...), this function might do the job: def hessian ( x, the_func, epsilon=1e-8): """Numerical approximation to the Hessian Parameters ---

[Numpy-discussion] Calculation of a hessian

2014-08-08 Thread Kiko
Hi all, I am trying to calculate a Hessian. I am using numdifftools for this ( https://pypi.python.org/pypi/Numdifftools). My question is, is it possible to make it using pure numpy?. The actual code is like this: *import numdifftools as nd* *import numpy as np* *def log_likelihood(params):*