## Sunday, August 4, 2024

### TI-84 Plus CE Python: Drawing Shapes with the ti_plotlib module

TI-84 Plus CE Python: Drawing Shapes with the ti_plotlib module

Introduction

Here are four scripts to draw shapes:

RECT8: rectangles and squares centered at (0, 0)

ELLIPSE8: ellipses and circles centered at (0, 0)

POLYGON8: polygons given the vertex points and number of vertices

INVFUNC8: draws a function f(x) and it’s inverse f^-1(x). Define the function is defined in the f(x) subroutine in the program.

The plot window is sized in sync with the TI-84’s screen size (320 pixels x 220 pixels) so that squares look like squares and circles look like circles. The window parameters are set as such:

Xmin = -16, Xmax = 16

Ymin = -10.5, Ymax = 10.5

TI-84 PLUS CE Python Script: RECT8.py

import ti_plotlib as plt

from math import *

# draw an rectangle using ti_plqtlib

# get parameters

print("Press [clear] to \nexit the graph.")

print("x:[-16,16] \ny:[-10.5,10.5]")

a=eval(input("horiz. length? "))

b=eval(input("vert. length? "))

# plot routine

plt.cls()

plt.title("Rectangle")

plt.window(-16,16,-10.5,10.5)

plt.axes("on")

plt.grid(1,1,"dot")

# color: blue

plt.color(0,0,192)

# pen size

plt.pen("medium","solid")

plt.line(-a/2,b/2,a/2,b/2,"")

plt.line(-a/2,-b/2,a/2,-b/2,"")

plt.line(-a/2,-b/2,-a/2,b/2,"")

plt.line(a/2,-b/2,a/2,b/2,"")

plt.show_plot()

TI-84 PLUS CE Python Script: ELLIPSE8.py

import ti_plotlib as plt

from math import *

# draw an ellipse using ti_plqtlib

# get parameters

print("Press [clear] to \nexit the graph.")

print("x:[-16,16] \ny:[-10.5,10.5]")

a=eval(input("x axis? "))

b=eval(input("y axis? "))

# plot routine

plt.cls()

plt.title("Ellipse")

plt.window(-16,16,-10.5,10.5)

plt.axes("on")

plt.pen("medium","solid")

plt.grid(1,1,"dot")

# color: green

plt.color(0,192,0)

for i in range(128):

x=a*cos(i*pi/64)

y=b*sin(i*pi/64)

plt.plot(x,y,"o")

plt.show_plot()

TI-84 PLUS CE Python Script: POLYGON8.py

import ti_plotlib as plt

from math import *

# draw an rectangle using ti_plqtlib

# get parameters

print("Press [clear] to \nexit the graph.")

print("x:[-16,16] \ny:[-10.5,10.5]")

n=int(input("# of vertices? "))

a=eval(input("x1? "))

b=eval(input("y1? "))

x=[a]

y=[b]

for i in range(n-1):

print("vertex ",i+2)

c=eval(input("x? "))

d=eval(input("y? "))

x.append(c)

y.append(d)

x.append(a)

y.append(b)

# plot routine

plt.cls()

plt.title("Polygon")

plt.window(-16,16,-10.5,10.5)

plt.axes("on")

plt.grid(1,1,"dot")

plt.color(75,0,130)

plt.pen("medium","solid")

for i in range(n):

x0=x[i]

y0=y[i]

x1=x[i+1]

y1=y[i+1]

plt.line(x0,y0,x1,y1,"")

plt.show_plot()

TI-84 PLUS CE Python Script: INVFUNC8.py

Define f(x) in the def f(x) function routine. The math module is imported.

import ti_plotlib as plt

from math import *

# f(x) and f**-1(x)

# define f(x)

def f(x):

return x**2+6

# plot routine

plt.cls()

plt.title("f(x) and its inverse")

plt.window(-16,16,-10.5,10.5)

plt.axes("on")

plt.grid(1,1,"dot")

plt.pen("medium","solid")

for i in range(320):

x=-16+i*32/320

y=f(x)

plt.color(0,0,192)

plt.plot(x,y,"o")

plt.color(255,165,0)

plt.plot(y,x,"o")

plt.show_plot()