# File:Surface normals.svg

Original file(SVG file, nominally 575 × 449 pixels, file size: 237 KB)

## Summary

Description
English: Normal vectors for the surface $xe^{-x^{2}-y^{2}}$ .
Español: Vectores normales a la superficie $xe^{-x^{2}-y^{2}}$ .
Date
Source Own work
Author Nicoguaro
SVG development

## Python

```import numpy as np
import matplotlib.pyplot as plt
from mpl_toolkits.mplot3d import Axes3D

x, y = np.mgrid[-1:1:31j, -1:1:31j]
xs, ys = np.mgrid[-1:1:9j, -1:1:9j]

z = x*np.exp(-x**2 - y**2)
zs = xs*np.exp(-xs**2 - ys**2)
u = -(1 - 2*xs**2)*np.exp(-xs**2 - ys**2)
v = 2*ys*zs
w = np.ones_like(xs)

fig = plt.figure()
ax = fig.add_subplot(111, projection='3d')
ax.view_init(azim=145, elev=45)
ax.plot_surface(x, y, z, rstride=1, cstride=1, cmap="summer", lw=0.3,
edgecolors="k")
ax.quiver(xs, ys, zs, u, v, w, colors='k', pivot='tail', length=0.3)
plt.axis("off")
plt.savefig("Surface normals.svg", bbox_inches="tight", transparent=True)
plt.show()
```

## Licensing

I, the copyright holder of this work, hereby publish it under the following license:  This file is licensed under the Creative Commons Attribution 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.

## File history

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Date/TimeThumbnailDimensionsUserComment
current01:16, 12 February 2016 575 × 449 (237 KB)NicoguaroUser created page with UploadWizard
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