task5Kutenev

#!/usr/bin/python
# -*- coding: utf8 -*-

import sys
import ROOT

def function(xx, pp):
    x = xx[0]
    A = pp[0]
    M = pp[1]
    G = pp[2]
    return (A * (G / 2)**2) / ((x - M)**2+(G / 2)**2)

g = ROOT.TGraphErrors("data.txt")

func = ROOT.TF1("f", function, 0.0,1.0, 3)

func.SetParameter(0, 1400)
func.SetParameter(1, 0.8)
func.SetParameter(2, 0.01)
func.SetLineColor(ROOT.kBlue)
g.Fit(func)
g.SetMarkerStyle(20)
canvas.cd(2)
g.Draw("AP")
sys.stdin.readline()

ROOT.gStyle.SetOptFit(1111)
fit_result = g.Fit("f", "S")

# Get value A, M, G
print " "
print "A:"
print "VALUE: ", func.GetParameter(0)
print "ERROR: ", func.GetParError(0)
print " "

print "M:"
print "VALUE: ", func.GetParameter(1)
print "ERROR: ", func.GetParError(1)
print " "

print "G:"
print "VALUE: ", func.GetParameter(2)
print "ERROR: ", func.GetParError(2)
print " "

# Correlation between parameters.
print "Correlation(A,M): ", fit_result.Correlation(0, 1)
print "Correlation(A,G): ", fit_result.Correlation(0, 2)
print "Correlation(M,G): ", fit_result.Correlation(0, 1)
print " "

# hi**2
print "Coefficient hi", fit_result.Chi2()/24.
print " "

canvas.Update()





histA = ROOT.TH1F("histA", "A", 50, 1420, 1540)
histM = ROOT.TH1F("histM", "M", 50, 0.783, 0.784)
histG = ROOT.TH1F("histG", "G", 50, 0.0085, 0.0092)

sigma_E = 0.1 / 1000
for i in range(0, 100):
    delta_E = ROOT.gRandom.Gaus(0, sigma_E)
    g2 = ROOT.TGraphErrors(t.GetEntries())
    for j in range(0, t.GetEntries()):
        sigma_epsilon = 0.01 * t.GetV1()[j] / 1.02
        delta_epsilon = ROOT.gRandom.Gaus(0, sigma_epsilon)
        E  = t.GetV1()[j] + delta_E
        Si = t.GetV2()[j] * (1 + delta_epsilon)
        g2.SetPoint(j, E, Si)
        g2.SetPointError(j, 0, t.GetV3()[i])
    fit_result2 = g2.Fit("f", "QS")
    histA.Fill(func.GetParameter(0))
    histM.Fill(func.GetParameter(1))
    histG.Fill(func.GetParameter(2))

print ""
print "A RMS:", histA.GetRMS()
print "M RMS:", histM.GetRMS()
print "G RMS:", histG.GetRMS()

canvas.cd(3)
histA.Draw()
canvas.cd(4)
histM.Draw()
canvas.cd(5)
histG.Draw()
sys.stdin.readline()



# закрыть файл
f.Close()