Dear Sir Now I figured out why there was a difference when I manually computed covariance and when I use the np. cov syntax in python.
The formula I used was ((yi-ymean)(yj-ymean))/n...unbiasdness. The formula np.cov uses is ((yi-ymean)(yj-ymean)) /n-1. Thanks Sincerely Meghna Raviraj Karkera On Mon, Oct 19, 2020, 21:30 Markos <mar...@c2o.pro.br> wrote: > Hi Meghna, > > I organized some tutorials about Machine Learning for Chemistry with > Python. > > Where you can find some info about the use of Covariance Matrix that may > help you. > > The originals are in Portugueese, but you can read using Google Translator: > > https://tinyurl.com/yybazx9n > > https://tinyurl.com/y29mule6 > > https://tinyurl.com/yxtg4tce > > Best Regards, > Markos > > Em 19-10-2020 02:23, Meghna Karkera escreveu: > > Dear Sir > > > > I am unable to find the *formula for covariance* used in np.cov syntax in > > PYTHON given in link > > https://numpy.org/doc/stable/reference/generated/numpy.cov.html. Could > you > > please help me out. > > > > Thanks > > Meghna > > > > On Tue, Oct 13, 2020 at 11:46 AM Christian Gollwitzer <aurio...@gmx.de> > > wrote: > > > >> Am 13.10.20 um 06:52 schrieb Meghna Karkera: > >>> Could you let me know what is the back end calculation of this > covariance > >>> matrix syntax np.cov > >>> > >> You can look it up yourself: Go to the docs > >> https://numpy.org/doc/stable/reference/generated/numpy.cov.html > >> > >> At the right hand side, just right of the function signature, there is a > >> link [source]. Click there and it takes you to the implementation. > >> > >> Apparently it is done in straightforward Python. > >> > >> Christian > >> > >> PS: Snipped a lot of unrelated citation at the bottom > >> > >>> On Tue, Oct 13, 2020, 10:14 Bruno P. Kinoshita < > >> brunodepau...@yahoo.com.br> > >>> wrote: > >>> [...] > >>>> I think the np.cov is from the numpy module (imported/aliased as np?). > >> -- > >> https://mail.python.org/mailman/listinfo/python-list > >> > > -- > https://mail.python.org/mailman/listinfo/python-list > -- https://mail.python.org/mailman/listinfo/python-list