File:QuadrupoleContour.svg
From KYNNpedia
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Original file (SVG file, nominally 540 × 540 pixels, file size: 158 KB)
Summary
| Description |
English: Contour plot of the equipotential surfaces of an electric quadrupole field. The field is accurately computed from a physical model. |
| Date | |
| Source | Own work |
| Author | Geek3 |
| SVG development |  This plot was created with Matplotlib. |
| Source code | Python codeimport numpy as np
from matplotlib import pyplot as plt
from matplotlib import colors
def simplify_contours(qcset, thresh=plt.rcParams['path.simplify_threshold']):
for c in qcset.collections:
paths = c.get_paths()
for i, p in enumerate(paths):
p.simplify_threshold = thresh / plt.gcf().dpi
paths[i] = p.cleaned(simplify=True)
xmax = 3.2
vmax = 4
levels = np.linspace(-vmax, vmax, 22)
X, Y = np.mgrid[-xmax:xmax:400j, -xmax:xmax:400j]
V = 1.0 / np.maximum(np.sqrt((X + 1)**2 + (Y + 1)**2), 1e-5)
V += 1.0 / np.maximum(np.sqrt((X - 1)**2 + (Y - 1)**2), 1e-5)
V -= 1.0 / np.maximum(np.sqrt((X + 1)**2 + (Y - 1)**2), 1e-5)
V -= 1.0 / np.maximum(np.sqrt((X - 1)**2 + (Y + 1)**2), 1e-5)
plt.figure(figsize=(6, 6)).add_axes([0, 0, 1, 1])
contf = plt.contourf(X, Y, V, levels=levels, cmap='RdBu_r', extend='both',
norm=colors.SymLogNorm(linthresh=1.5, vmin=-vmax, vmax=vmax))
simplify_contours(contf, plt.rcParams['lines.linewidth'])
cont = plt.contour(X, Y, V, levels=contf.levels, colors='k', linestyles='solid')
plt.xticks([]), plt.yticks([])
plt.gca().set_aspect(aspect='equal')
plt.gca().axis('off')
for i in -1,1:
for j in -1,1:
plt.text(i, j, {-1:u'\u2212', 1:'+'}[i*j],
size=18, ha='center', va='center')
plt.savefig('QuadrupoleContour.svg')
|
Licensing
I, the copyright holder of this work, hereby publish it under the following license:
This file is licensed under the Creative Commons Attribution-Share Alike 4.0 International license.
- You are free:
- to share – to copy, distribute and transmit the work
- to remix – to adapt the work
- Under the following conditions:
- attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use.
- share alike – If you remix, transform, or build upon the material, you must distribute your contributions under the same or compatible license as the original.
File history
Click on a date/time to view the file as it appeared at that time.
| Date/Time | Thumbnail | Dimensions | User | Comment | |
|---|---|---|---|---|---|
| current | 22:52, 14 May 2018 | | 540 × 540 (158 KB) | wikimediacommons>Geek3 | Potential must be 1/r, not 1/r². |
File usage
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