This well commented Python snippet uses wxPython's plotting widget to graph the projectile motion of two different firing angles on the same plotting canvas.

193 Views
``````# using wxPython for plotting projectile motion
# draw line graph for 2 different firing angles
# tested with Python25 and wxPython28  vegaseat   26mar2008

import wx
import wx.lib.plot as plot
import math

class MyFrame(wx.Frame):
def __init__(self):
self.frame1 = wx.Frame(None, title="wx.lib.plot", id=-1, size=(410, 340))
self.panel1 = wx.Panel(self.frame1)
self.panel1.SetBackgroundColour("yellow")
# set up the plot canvas
plotter = plot.PlotCanvas(self.panel1)
plotter.SetInitialSize(size=(400, 300))
# enable the zoom feature (drag a box around area of interest)
plotter.SetEnableZoom(True)

# projectile motion equations:
# height = y(t) = h0 + (t * v * sin(a)) - (g * t*t)/2
# range  = x(t) = v * cos(a) * t
# where:
# v is the muzzle velocity of the projectile (meter/second)
v = 100
# a is the firing angle with repsect to ground (radians)
# h0 is starting height with respect to ground (meters)
h0 = 0
# g is the gravitational pull (meters/second_square)
g = 9.8

# now calculate the list of (x, y) data point tuples ...
# x axis is range (distance) in meters
# y axis is height in meters
# first for a firing angle of 45 degrees
d = 45
data45 = []
for t in range(0, 200):
# use the time in increments of tx (0.1) seconds
tx = t/10.0
# now calculate the height y
y = h0 + (tx * v * math.sin(a)) - (g * tx * tx)/2
# calculate the range x
x = v * math.cos(a) * tx
# append the (x, y) tple to the list
data45.append((x, y))

# now for a firing angle of 30 degrees
d = 30
data30 = []
for t in range(0, 200):
# use the time in increments of tx (0.1) seconds
tx = t/10.0
# now calculate the height y
y = h0 + (tx * v * math.sin(a)) - (g * tx * tx)/2
# calculate the range x
x = v * math.cos(a) * tx
# append the (x, y) tuple to the data list
data30.append((x, y))

# draw points as a line
# 2 different lines one for an angle of 45 one of 30 degrees
line45 = plot.PolyLine(data45, colour='red', width=1)
line30 = plot.PolyLine(data30, colour='blue', width=1)
# set up the plot
gc = plot.PlotGraphics([line45, line30],
'Projetile Motion',
'range (meters) firing angle red=45, blue=30',
'height (meters)')
# and draw it
plotter.Draw(gc, xAxis=(0,1200), yAxis=(0,300))

self.frame1.Show(True)

app = wx.PySimpleApp()
f = MyFrame()
app.MainLoop()``````