File:Curve fitting.svg
Summary
| Description |
English: This graph shows a series of points (generated by a Sin function) approximated by polinomial curves (red curve is linear, green is quadratic, orange is cubic and blue is 4th degree).
Italiano: Il grafo mostra una serie di punti (generati dalla funzione seno) approssimati da curve polinomiali (in rosso di primo grado, verde di secondo, arancione di terzo e verde di quarto. |
| Date | |
| Source | Own work |
| Author | Krishnavedala |
| Other versions | File:Curve fitting.jpg |
W3C-validity not checked.
GNU Octave source code |
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x = 1:1.5:100;
y = sin(x/10);
p1 = polyfit(x,y,1);
p2 = polyfit(x,y,2);
p4 = polyfit(x,y,4);
p3 = polyfit(x,y,3);
figure;
plot(x,y,'k.'); hold all
plot(x,polyval(p1,x),'r');
plot(x,polyval(p2,x),'g');
plot(x,polyval(p3,x),'color',[1 .5 0]);
plot(x,polyval(p4,x),'b');
grid on
set (gca,'xaxislocation','zero')
set (gca,'yaxislocation','zero')
box off
print('Curve fitting.svg')
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Python source Code |
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Created using python with numpy and matplotlib toolboxes. from numpy import *
from matplotlib.pyplot import *
from mpl_toolkits.axes_grid.axislines import SubplotZero
x = linspace(0,100,75)
y = sin(2.*pi*x/60.+.4)
y1 = poly1d(polyfit(x,y,1)) # linear
y2 = poly1d(polyfit(x,y,2)) # quadratic
y3 = poly1d(polyfit(x,y,3)) # cubic
y4 = poly1d(polyfit(x,y,4)) # 4th degree
fig = figure(figsize=(6,4))
ax = SubplotZero(fig,111)
fig.add_subplot(ax)
ax.grid(True)
ax.plot(x,y1(x),'r',label=u'linear')
ax.plot(x,y2(x),'g',label=u'quadratic')
ax.plot(x,y3(x),'orange',label=u'cubic')
ax.plot(x,y4(x),'b',label=u'$4^{th}$ order')
ax.plot(x,y,'k.',label=u'data')
ax.set_xlabel(u'x')
ax.set_ylabel(u'y')
ax.minorticks_on()
ax.legend(frameon=False,loc=4,labelspacing=.2)
setp(ax.get_legend().get_texts(), fontsize='small')
fig.savefig("Curve fitting.svg",bbox_inches="tight",pad_inches=.15)
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Licensing
I, the copyright holder of this work, hereby publish it under the following license:
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This file is made available under the Creative Commons CC0 1.0 Universal Public Domain Dedication. |
| The person who associated a work with this deed has dedicated the work to the public domain by waiving all of their rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law. You can copy, modify, distribute and perform the work, even for commercial purposes, all without asking permission.
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