#!/usr/bin/env python
# coding: utf-8

# # Reading points from a file and produce a graph

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from ROOTaaS.iPyROOT import ROOT
ROOT.toCpp()


# Let's inspect the input file, which is in the appropriate format for filling a TGraphErrors

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.! cat macro2_input.txt


# Now, let's start with the creation of the graphs as well as some beautification

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auto c=new TCanvas();c->SetGrid();
TGraphErrors graph_expected("./macro2_input_expected.txt","%lg %lg %lg");
graph_expected.SetTitle("Measurement XYZ and Expectation;lenght [cm];Arb.Units");
graph_expected.SetFillColor(kYellow);
graph_expected.DrawClone("E3AL"); // E3 draws the band

TGraphErrors graph("./macro2_input.txt","%lg %lg %lg");
graph.SetMarkerStyle(kCircle);
graph.SetFillColor(0);
graph.DrawClone("PESame");


# We add a legend to improve the clarity of the plot. It is always reccomended to make the plot "self descriptive".

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TLegend leg(.1,.7,.3,.9,"Lab. Lesson 2");
leg.SetFillColor(0);
leg.AddEntry(&graph_expected,"Expected Points");                                                                                          
leg.AddEntry(&graph,"Measured Points");                                                                                                   
leg.DrawClone("Same");


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