Folks,
I’m seeing a bug in fitting code, using TMinuit from python. My code worked fine in V5.26.00, and sees the problem in V5.30.00. I also find that TMinuit from C++ is fine, only the python interface sees the bug.
The sample code below shows the problem: when there are floating parameters, the array of parameters passed to FCN has a size equal to the number of floating parameters, but it should be all parameters.
In the sample code below I have 4 parameters. The fit is fine when all are floating, but if I fix one of them I find that the parameter array passed to FCN now has dimensions of the number of floating parameters. I tried a C++ version of this sample code and it worked fine in both cases.
example.py (1.74 KB)
To see the problem:
execfile(“example.py”)
Ifit(False) # its ok
Ifit(True) # crashes
thanks,
Aaron