def fitLambda():
data = Data()
data.addPoint(500, 1.000279)
data.addPoint(540, 1.000278)
data.addPoint(600, 1.000277)
data.addPoint(682, 1.000276)
c = TCanvas('c1', '', 1280, 720)
g = data.makeGraph('g', 'wavelength #lambda / nm', 'refraction index n')
g.GetYaxis().SetLabelSize(0.03)
g.GetYaxis().SetTitleOffset(1.39)
g.Draw('AP')
fit = Fitter('f', '[0]+[1]*x')
fit.setParam(0, 'a', 2)
fit.setParam(1, 'b', -1)
fit.fit(g, 450, 700)
fit.saveData('../calc/fit_lambda.txt', 'w')
a = fit.params[0]['value']
sa = fit.params[0]['error']
b = fit.params[1]['value']
sb = fit.params[1]['error']
l = TLegend(0.4, 0.6, 0.87, 0.87)
l.AddEntry('g', 'refraction index n as a function of wavelength #lambda', 'p')
l.AddEntry(fit.function, 'fit with n(#lambda)= a+b*#lambda', 'l')
fit.addParamsToLegend(l)
l.SetTextSize(0.03)
l.Draw()
c.Update()
c.Print('../img/fit_lambda.pdf', 'pdf')
def makePolarPlot(squiddata, name, omega, phi, si, offset):
# generate polar data
data = Data()
for t, A, st, sA in squiddata.points:
alpha = omega * t + phi
B = abs(ampToB(si, A - offset, sA)[0])
x = B * np.cos(alpha)
y = B * np.sin(alpha)
data.addPoint(x, y)
# make canvas and graph
c = TCanvas('c_polar_%s' % name, '', 1280, 1280)
g = data.makeGraph('g_polar_%s' % name, 'B_{z} / T', 'B_{z} / T')
g.SetMarkerStyle(1)
g.Draw('AP')
# set quatratic range
gPad.Update()
ymin = gPad.GetUymin()
ymax = gPad.GetUymax()
xmin = gPad.GetUxmin()
xmax = gPad.GetUxmax()
posdim = max(xmax, ymax)
negdim = min(xmin, ymin)
g.SetMinimum(negdim)
g.SetMaximum(posdim)
g.GetXaxis().SetLimits(negdim, posdim)
# draw axis cross
vline = TLine(0, negdim, 0, posdim)
vline.Draw()
hline = TLine(negdim, 0, posdim, 0)
hline.Draw()
# print canvas
c.Update()
c.Print('../img/polar_%s.pdf' % name, 'pdf')
