Multiplying two polynomial functions

ROOT
1

I have two polN functions which I multiply in a third function:

f11 = TF1('f11','pol1',0,10)
f11.SetParameter(0,1)
f11.SetParameter(1,0.05)

f21 = TF1('f21','pol0',0,10)
f21.SetParameter(0,1.5)

f31 = TF1('f31','f11*f21',0,10)

However, when plotting, f31 is the same as f11. Why is that?

When I create the polN function by hand ([0]+x*[1] etc.) then multiplication
works as expected.

Full example attached.
combinefunctions.py (1.1 KB)

2

Search for “polN” In the TF1 class description. :stuck_out_tongue: