Topher, > I can't do anything much with gMinuit though. I'd have expected the > following to print out the covariance matrix, for example: > >>> gMinuit.mnexcm("SHO COV") > Traceback (most recent call last): > File "<stdin>", line 1, in ? > SystemError: NULL result without error in PyObject_Call > Seems like all other (useful) methods of gMinuit have similar problems. > GetName() works. The mnexcm() function has the following signature: void mnexcm(const char* comand, Double_t* plist, Int_t llist, Int_t& ierflg) calling it requires something like: from array import array plist = array('d',9*[0]) ierflg = array('i',[0]) gMinuit.mnexcm( "SHO COV", plist, 9, ierflg ) Admittedly, the error message that you got wasn't very helpful. This has been fixed (should appear in CVS shortly). > Another thing that doesn't work but should: > >>> covm = ROOT.TMatrixD(3, 3, fitter.GetCovarianceMatrix()) > Traceback (most recent call last): > File "<stdin>", line 1, in ? > TypeError: None of the 15 overloaded methods succeeded This is a bug and has been fixed (should appear in CVS shortly). In the mean time, you can do: covm = fitter.GetCovarianceMatrix() and access the elements as a straight array: covm[0] through covm[8]. HTH, Wim -- Wim.Lavrijsen@cern.ch -- WLavrijsen@lbl.gov -- www.lavrijsen.net "Stop making excuses for your software." --first step towards quality
This archive was generated by hypermail 2b29 : Sun Jan 02 2005 - 05:50:09 MET