FROM TH2F
constant
1.3108661236287613+-0.1330954809168955
chi2/ndof = 3.5090684488383594
plane
-5.955304745317521+-2.267719589256051
invpt slope = -0.8357090540342097+-0.08318264514103145
theta slope = 9.755393179794893+-1.7541109374018569
chi2/ndof = 1.1354584980038191
from tgraph2D
constant
4.792252426284131+-0.12486534218289062
chi2/ndof = 1.2628996475656558
plane
3.917199477717519+-1.1912775108421323
invpt slope = -0.1512899377401725+-0.04507076053790602
theta slope = 1.0855661376362864+-0.9434732794232625
chi2/ndof = 1.1274141181435682