VPython Reference

Created by Shuyang Chen

VPython reference page for animation functions and constants. This page assumes and only includes basic usage of VPython.

VPython Template

from __future__ import division
from visual import *

## Constants

## Initialization

## Loop
t = 0
deltat = 1e-10
end = 10

while t < end:
    rate(1000)
    ## Loop Code
    
    t += deltat

VPython Animation Functions

Sphere

Source

Example

ball = sphere(pos=(1,2,3), radius=0.4, color=color.blue)

Parameters

Parameter	Type	Description
pos	vector	Position of the object
color	color	Color of the object
radius	number	Radius of the sphere
opacity	number	Opacity of the object
make_trail	boolean	Whether or not to leave behind a trail

Arrow

Source

Example

arr = arrow(pos=(1,2,3), axis=(4,5,6), color=color.red)

Parameters

Parameter	Type	Description
pos	vector	Position of the object
axis	vector	Direction the arrow is pointing at
color	color	Color of the object
opacity	number	Opacity of the object
shaftwidth	number	Width of the shaft (default: 0.1*(length of arrow))
headwidth	number	Width of the head (default: 2*shaftwidth)
headlength	number	Length of the head (default: 3*shaftwidth)
make_trail	boolean	Whether or not to leave behind a trail

Color

Source

Example

c = color.red

Basic Colors

Name	Vector	Color
Red	(1,0,0)	color.red
Yellow	(1,1,0)	color.yellow
Green	(0,1,0)	color.green
Orange	(1,0.5,0)	color.orange
Blue	(0,0,1)	color.blue
Cyan	(0,1,1)	color.cyan
Magenta	(1,0,1)	color.magenta
White	(1,1,1)	color.white
Black	(0,0,0)	color.black

VPython Common Constants

Constants

Constant	Common Variable Name	Approximate Value	Code
Speed of light	c	299792458.0	c = 299792458.0
Gravitational Constant	G	6.67408e-11	G = 6.67408e-11
Electron Mass	m_e	9.10938356e-31	m_e = 9.10938356e-31
Proton Mass	m_p	1.6726219e-27	m_p = 1.6726219e-27
Neutron Mass	m_n	1.674927471e-27	m_n = 1.674927471e-27
Electric Constant	oofpez	8.9875517873681764e9	oofpez = 8.9875517873681764e9
Permitivity of Free Space	e0	8.854187817e-12	e0 = 8.854187817e-12
Magnetic Constant	[math]\displaystyle{ \frac{\mu_0}{4\pi} }[/math]	[math]\displaystyle{ 1 \times 10^{-7} }[/math]	[math]\displaystyle{ T\cdot m/A }[/math]
Vacuum Permeability	[math]\displaystyle{ \mu_0 }[/math]	[math]\displaystyle{ 4\pi \times 10^{-7} }[/math]	[math]\displaystyle{ T\cdot m/A }[/math]
Proton Charge	[math]\displaystyle{ e }[/math]	[math]\displaystyle{ 1.6 \times 10^{-19} }[/math]	[math]\displaystyle{ C }[/math]
Electron Volt	[math]\displaystyle{ eV }[/math]	[math]\displaystyle{ 1.6 \times 10^{-19} }[/math]	[math]\displaystyle{ J }[/math]
Avogadro's Number	[math]\displaystyle{ N_A }[/math]	[math]\displaystyle{ 6.02 \times 10^{23} }[/math]	[math]\displaystyle{ molecules/mole }[/math]
Atomic Radius (approximate)	[math]\displaystyle{ R_a }[/math]	[math]\displaystyle{ 1 \times 10^{-10} }[/math]	[math]\displaystyle{ m }[/math]
Proton Radius	[math]\displaystyle{ R_p }[/math]	[math]\displaystyle{ 1 \times 10^{-15} }[/math]	[math]\displaystyle{ m }[/math]
E to ionize air	[math]\displaystyle{ E_{ionize} }[/math]	[math]\displaystyle{ 3 \times 10^{6} }[/math]	[math]\displaystyle{ V/m }[/math]
Earth's Magnetic Field	[math]\displaystyle{ B_{Earth} }[/math]	[math]\displaystyle{ 2 \times 10^{-5} }[/math]	[math]\displaystyle{ T }[/math]

Connectedness

1. How is this topic connected to something that you are interested in?
2. How is it connected to your major?
3. Is there an interesting industrial application?

History

Put this idea in historical context. Give the reader the Who, What, When, Where, and Why.

See also

Are there related topics or categories in this wiki resource for the curious reader to explore? How does this topic fit into that context?

Further reading

Books, Articles or other print media on this topic

External links

[1]

References

This section contains the the references you used while writing this page