FROM TH2F
constant
18.73553818148792+-0.48093964312726456
chi2/ndof = 3.444745712147435
plane
4.436600489742038+-1.1400837596181606
invpt slope = 6.7451724248032745+-0.6369113618149118
theta slope = 13.248606128254071+-1.577811847657174
chi2/ndof = 1.0257010220397662
from tgraph2D
constant
20.594356463309733+-0.9964743879675808
chi2/ndof = 96.31723680281658
plane
5.6512057780017715+-1.2856180255245993
invpt slope = 7.211968219600219+-0.6450239760193023
theta slope = 12.547273006404364+-1.747581378829476
chi2/ndof = 32.48107564298878