Python: draw tangent graph using math & turtle libraries

Question

I was stuck on this task for several days. Although, the solution should be simple. I apply math and turtle libraries for drawing 3 graphs: sine, cosine and tangent with amplitude 200. The problem is I cant build the tangent graph as It should be drawn. This is what I should do:

This is what I got:

As you see, my turtle goes up and doesn't come back anymore. Pls, don't suggest me to use numpy. It's out of my task. Thank you for advance!

import math
import turtle

ws = turtle.Screen()
ws.bgcolor("white")
t = turtle.Turtle()
for i in [(0,250), (0,0), (0,-250), (0,0), (400,0), (0,0)]:
    t.goto(i, None)
    t.write(i, font=("Arial", 12))

t.color("red")

for angle in range(360):
    y = math.sin(math.radians(angle))        
    t.goto(angle, y * 200)

t.penup()
t.setpos(0,200)
t.goto(0,200)
t.pendown()
t.color("blue")

for angle in range(360):
    y = math.cos(math.radians(angle))       
    t.goto(angle, y * 200)

t.penup()
t.setpos(0,0)
t.goto(0,0)
t.pendown()
t.color("green")

for angle in range(360):
    y = math.tan(math.radians(angle))
    t.goto(angle, y * 200)

ws.exitonclick()

Answer 1

To show that it should work, below is my minimalist implementation of plotting sine, cosine and tangent using turtle graphics:

import math
from turtle import Turtle, Screen

RESOLUTION = 0.1

def plot(x_points, y_points):
    for i, y in enumerate(y_points):
        if abs(y) <= 2.0:
            yertle.goto(x_points[i], y)
            yertle.pendown()
        else:
            yertle.penup()

    yertle.penup()

screen = Screen()
screen.setworldcoordinates(0, -1.5, 2 * math.pi / RESOLUTION, 1.5)

yertle = Turtle()
yertle.penup()

x = range(int(2 * math.pi / RESOLUTION))

yertle.color("blue")
plot(x, (math.cos(n * RESOLUTION) for n in x))

yertle.color("red")
plot(x, (math.sin(n * RESOLUTION) for n in x))

yertle.color("dark green")
plot(x, (math.tan(n * RESOLUTION) for n in x))

screen.exitonclick()

OUTPUT

My guess is you're not waiting long enough for tangent to plot, ie it's slowly plotting lots of points off the window and will eventually reappear on-screen. My code works around that issue.

Answer 2

try about this. Near to work for me, no time to get better:

for angle in range(360): y=0

y = math.tan(math.radians(angle))
if y<1 and y>-1:
    t.goto(angle, y * 200)

Answer 3

With asipmtotas

for angle in range(360):
    t.penup()
    y = math.tan(math.radians(angle))

    if y<1 and y>-1:
        t.pendown()
        t.goto(angle, y * 200)
    else:
        t.penup()
        #t.pendown()
        t.goto(angle, 200)