File:Interpolation example spline.svg

Summary[edit]

Based on png-version by User:Jitse Niesen (with gnuplot source code), and on svg-version by User:Cronholm144.

Gnuplot source code[edit]

set terminal svg fname "Vera" fsize 25
set output "Interpolation_example_spline.svg"
set key off
set xzeroaxis
set xtics axis 1,1
set ytics nomirror 1
set samples 300
set border 2
f(x) = (x >= 0 && x < 1) ? -0.1522*x**3 + 0.9937*x : \
       (x >= 1 && x < 2) ? -0.01258*x**3 - 0.4189*x**2 + 1.4126*x - 0.1396 : \
       (x >= 2 && x < 3) ? 0.1403*x**3 - 1.3359*x**2 + 3.2467*x - 1.3623 : \
       (x >= 3 && x < 4) ? 0.1579*x**3 - 1.4945*x**2 + 3.7225*x - 1.8381 : \
       (x >= 4 && x < 5) ? 0.05375*x**3 -0.2450*x**2 - 1.2756*x + 4.8259 : \
                           -0.1871*x**3 + 3.3673*x**2 - 19.3370*x + 34.9282 
set yrange [-1.1:1.1]
plot f(x) with lines linetype 3 linewidth 4, \
     "-" with points linetype 1 pointtype 7 pointsize 0.7,\
	 0 with lines linetype -1 linewidth 1
0 0
1 0.8415
2 0.9093
3 0.1411
4 -0.7568
5 -0.9589
6 -0.2794
e

Please use at least version 4.2 of Gnuplot for smooth lines in SVG.

Licensing[edit]

This work has been released into the public domain by its author, I, Berland. This applies worldwide. In some countries this may not be legally possible; if so: I, Berland grants anyone the right to use this work for any purpose, without any conditions, unless such conditions are required by law.