ROOT
6.12/07
Reference Guide
tutorials
math
Legendre.py
Go to the documentation of this file.
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## \file
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## \ingroup tutorial_math
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## \notebook
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## Example of first few Legendre Polynomials. Inspired by work of Lorenzo Moneta.
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##
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## \macro_image
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## \macro_code
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##
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## \author Alberto Ferro
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import
ROOT
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ROOT.gSystem.Load(
"libMathMore"
)
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Canvas = ROOT.TCanvas(
"DistCanvas"
,
"Legendre polynomials example"
, 10, 10, 750, 600)
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Canvas.SetGrid()
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leg = ROOT.TLegend(0.5, 0.7, 0.4, 0.89)
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L = []
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for
nu
in
range(5):
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f = ROOT.TF1(
"L_0"
,
"ROOT::Math::legendre([0],x)"
, -1, 1)
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f.SetParameters(nu, 0.0)
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f.SetLineStyle(1)
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f.SetLineWidth(2)
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f.SetLineColor(nu+1)
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L.append(f)
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L[0].SetMaximum(1)
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L[0].SetMinimum(-1)
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L[0].SetTitle(
"Legendre polynomials"
)
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leg.AddEntry(L[0].
Draw
(),
" L_{0}(x)"
,
"l"
)
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leg.AddEntry(L[1].
Draw
(
"same"
),
" L_{1}(x)"
,
"l"
)
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leg.AddEntry(L[2].
Draw
(
"same"
),
" L_{2}(x)"
,
"l"
)
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leg.AddEntry(L[3].
Draw
(
"same"
),
" L_{3}(x)"
,
"l"
)
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leg.AddEntry(L[4].
Draw
(
"same"
),
" L_{4}(x)"
,
"l"
)
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leg.Draw()
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Draw
th1 Draw()