File:Langevin+expansions.svg

Summary

Description
English: The Langevin function (red) and two approximations for small x: a truncation of it's continued fraction expansion (green), and a truncation of it's Taylor series (blue)
Français : Fonction de Langevin (rouge), avec deux approximations pour des petits x : développement en fraction continue tronqué (vert), et développement limité à l'ordre 3 (en bleu)
Date
Source Own work
Author Edgar Bonet

Gnuplot source

#!/usr/bin/gnuplot

# Langevin function and two expansions

set term svg size 640, 480 enhanced font "Times,13"
set output "langevin+expansions.svg"
set xlabel "x" offset 0, 0.5
set xrange [-12:12]
set xtics ("−10" -10, "−5" -5, 0, 5, 10)
set yrange [-1:1]
set ytics ("−1" -1, "−0,5" -0.5, 0, "0,5" 0.5, 1)
set lmargin 6
set grid lt 1 lc rgbcolor "#cccccc"
set key top left Left reverse invert spacing 1.3 width -5
set samples 200
set style line 3 lw 3.0 lc rgbcolor "#cc0000"
set style line 2 lw 1.5 lc rgbcolor "#00ff00"
set style line 1 lw 1.5 lc rgbcolor "#9999ff"
set style increment user

plot x/3 - x**3/45 title "x/3 − x³/45", \
     x/(3 + x*x/5) title "x/(3 + x²/5)", \
     x==0 ? 0 : 1/tanh(x)-1/x title "L(x)"

Licensing

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w:en:Creative Commons
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Category:CC-BY-SA-3.0#Langevin+expansions.svgCategory:Self-published work
Category:Images with Gnuplot source code Category:Statistical mechanics Category:Magnetization curves Category:Paramagnetism Category:Taylor series Category:Langevin function
Category:CC-BY-SA-3.0 Category:Images with Gnuplot source code Category:Langevin function Category:Magnetization curves Category:Paramagnetism Category:Self-published work Category:Statistical mechanics Category:Taylor series Category:Unspec SVG created with Gnuplot