Develop Reference

Drawing staircases in a loop but not getting correct results

I am trying to draw 7 staircases with a loop but I have missed something and not sure why it's not working. It draws the first staircase and then goes completely off track and doesn't put the pen back down and I'm not sure why.
#Draw stairs 7 times
from turtle import*
#Stair repeat
for i in range (3):
forward (25)
left (90)
forward(25)
right(90)
#move to next stair
for i in range(7):
penup()
forward(25)
right(90)
forward(75)
left(90)
pendown()
My understanding is that the for loop would repeat the code, so if I want it to move for 7 separate stairs then the range is 7? This is obviously not correct though as it doesn't work. Hoping someone could point me in the correct direction as to why it's wrong.

A couple things seem amiss:
The body of the for i in range(7): loop doesn't make sense. It never does any movement when the pen is down, so the turtle draws nothing.
The for i in range (3): loop doesn't make sense either if you want to draw 7 stairs. What do you need to do 3 times here?
Beyond that, avoid from turtle import *. This is confusing and can lead to bugs, because it brings hundreds of functions into your namespace, creating potential name clashes and making it hard to tell which functions are yours and which belong to the turtle module. Better to import turtle or from turtle import Screen, Turtle and create a turtle instance.
Here's a rework that hopefully matches your intended result:
import turtle
t = turtle.Turtle()
step_size = 25
for _ in range(7):
t.left(90)
t.forward(step_size)
t.right(90)
t.forward(step_size)
turtle.exitonclick()
Based on the follow-up comment, if you want to draw staircases of 3 stairs 7 times, then nest your loops and add some code to reposition the turtle to wherever it needs to be to draw each staircase. For example:
import turtle
t = turtle.Turtle()
step_size = 25
for i in range(7):
t.penup()
# whatever logic puts you in the right position for the next stair
t.goto(-step_size * i, 1.5 * step_size * i)
t.pendown()
for _ in range(3):
t.left(90)
t.forward(step_size)
t.right(90)
t.forward(step_size)
turtle.exitonclick()
I don't know what your expected goal is, so you'll need to adjust this to match that, but the general approach should be the same.

How can I rotate a shape from the bottom in turtle

I am trying to make a turtle analog clock, and to make the second, minute, an hour hands I am making a shape with turtle, and using .tilt() to tilt it 6 degrees every second.
The thing is, when I run .tilt() it rotates the ship from the middle, whereas I want to have it rotate from the bottom point (like an analog clock).
Is there a way to do that, or do I need to find another way to make this program?
Here is my code:
from turtle import *
import time
turtle = Turtle()
turtle.shape("square")
turtle.shapesize(6, .1)
tilt_amnt = 0
for x in range (60):
turtle.tilt(tilt_amnt)
tilt_amnt = tilt_amnt + 6
time.sleep(1)

I don't think there is a way to tilt the turtle in such a way where it turns from the bottom but you can rewrite the code to essentially do the same thing but using forward instead. Check this out.
from turtle import *
import time
turtle = Turtle()
turtle.pensize(2)
turtle.hideturtle()
turtle.speed(0)
tilt_amnt = 0
for x in range (60):
turtle.right(tilt_amnt)
turtle.forward(100)
turtle.backward(100)
tilt_amnt = tilt_amnt + 6
time.sleep(1)
turtle.clear()

Some thoughts: first, I wouldn't use tilt() (high overhead, forces an update), even if you do use turtles as hands, consider using right() or setheading(); second, I would use mode('logo') as this makes 0 degrees the top of the screen and makes headings clockwise (like, say a 'clock') instead of counterclockwise; third, if you want accuracy, don't use sleep() but rather extract the current time from the system and set your hands accordingly.
Large real world clocks do turn their hands from the middle, or more specifially, the center of gravity. This keeps the hands from slowing the mechanism on the way up, or rushing it on the way down. The trick is to make the hands look visually asymmetric but keep the weight symmetric. Here's a solution I came up with earlier that does something like this with turtles as the hands, turning from their centers.
Finally, here's a rewrite of the example #AlexJoslin provided to use realtime accuracy, potentially updating hand positions multiple times within a second:
from turtle import Screen, Turtle
from time import localtime as time
def tick():
second.setheading(6 * time().tm_sec)
second.clear()
second.forward(150)
second.backward(150)
screen.update()
screen.ontimer(tick)
screen = Screen()
screen.mode('logo')
screen.tracer(False)
second = Turtle()
second.hideturtle()
second.pensize(2)
tick()
screen.exitonclick()

How to add physics to a turtle in python

I'm creating a game in python that you can move around and try to collect points by colliding with a coin. I want to add 2D physics to it to make it realistic. Is there any way to do that? Thanks

The nature of simulations is that they are different than reality. As we perform a simulation, we create a mathematical model of the behavior of objects. Let's consider simulation of gravity. We define a ball, then we displace the location of the ball as time flows. Newton modeled the falling of a ball by x=gt^2. Therefore we must define an acceleration for the ball towards the ground. Much more information about simulation is available in this video.
You can use this code in order to simulate gravity:
yvel=5*(time()-start_t)
where time() cames from from time import time

This is how to do it:
The explanation is inside the code.
#Importing all the modules
import turtle
from turtle import *
import math
#Creating the screen
screen=Screen()
#Creating the turtle
vector1=Turtle("classic")
vector1.speed(-1)
vector1.penup()
#Declaring all the needed variables
Vx=0
Vy=0
V=0
A=0
#Starting the while loop
while True:
#Updating the screen for better preformence
screen.update()
#Carculating the velocity
V=math.sqrt(Vx**2+Vy**2)
#Carculating the angle
if Vx!=0:
A=math.degrees(math.atan(Vy/Vx))
if Vy<0 and Vx<0 or Vy>0 and Vx<0:
A=A-180
elif Vy <0:
A=270
else:
A=90
#Moving the turtle
vector1.seth(A)
vector1.fd(V)
#Changing the values of the velocities
Vy-=0.5
if Vx>0:
Vx-=0.2
elif Vx<0:
Vx+=0.2
If there are any questions, please ask!

Drawing an array of shapes using Turtle, but only one showing up

I'm trying to draw a bunch of squares using Turtle, but only the last one shows up instead of two. (I'm planning to add more, but i'm stuck on this)
wall = []
block = turtle.Turtle()
block.shape("square")
block.color("black")
block.penup()
wall.append(block)
wall.append(block)
wall[0].goto(20, 20)
wall[1].goto(40, 40)
Please let me know if you need any additional info and thank you for taking a look.

You have created just a single turtle, but then put two references to that one turtle in your list wall. You would need to create turtles in a loop to populate wall if you want your list to consist of distinct turtles:
import turtle
wall = []
for i in range(2):
block = turtle.Turtle()
block.shape("square")
block.color("black")
block.penup()
wall.append(block)
wall[0].goto(20, 20)
wall[1].goto(40, 40)
should work as expected.
Another approach, is to forget wall completely, stick to a single turtle, but have it stamp its shape where you want:
block = turtle.Turtle()
block.shape("square")
block.color("black")
block.penup()
block.goto(20, 20)
block.stamp()
block.goto(40, 40)
block.stamp()
which gives the same visual pattern as the first code.
If the intention is to have a wall of blocks, you could do this in a loop:
for x in range(-260,280,20):
block.goto(x, x)
block.stamp()
will draw a diagonal wall of squares across the turtle screen.

Drawing circles based on user input

I am writing a Python code for a school project. The program is to draw a number of circles based on the user input, (2-6 circles). I have done that but now need to draw multiple rows of circles based on user input. For example, if a user picks 3 circles I need to draw 3 circles by 3 circles.
#import tkinter and turtle
import tkinter as tk
from turtle import *
#ask for user input using tkinter
from tkinter import simpledialog
application_window = tk.Tk()
answer = simpledialog.askinteger('Request', 'number of circles(2-6)?',
parent=application_window, minvalue=2, maxvalue=6)
#set position of turtle and define turtle
t = Turtle()
t.penup()
t.setpos(-200,-200)
t.pendown()
#draw appropriate number of circles using loop
i = 2
for i in range (answer):
circle(30)
penup()
forward(60)
pendown()
i = +1

Don't make us do your homework. Tell us the problem, tell us what you've tried, then ask a question. For example, "How do I make the turtle draw three rows of circles?"
Surround the for loop you already have with another for loop. Every time the outer loop runs, the inner loop will run to create one row, and then move the turtle down before the next iteration.
#import tkinter and turtle
import tkinter as tk
from turtle import *
#ask for user input using tkinter
from tkinter import simpledialog
application_window = tk.Tk()
answer = simpledialog.askinteger('Request', 'number of circles(2-6)?',
parent=application_window, minvalue=2, maxvalue=6)
#set position of turtle and define turtle
t = Turtle()
t.penup()
t.setpos(-200,-200)
t.pendown()
#draw appropriate number of circles using loop
for row in range(answer):
for col in range(answer):
circle(30)
penup()
forward(60) # must be undone after loop
pendown()
penup()
backward(60) # undo the backward on line 20
backward(60 * col) # go backwards the length of the diameter times the number of circles
right(90) # turn right 90 degrees
forward(60) # forward the length of one diameter
left(90) # turn back left 90 degrees
pendown()

I'm offering an alternate solution to that of #JacksonH for two reasons: first, if you're using Python 3 (and you should be), then you don't need to grab simpledialog out of tkinter, use Python 3 turtle's numinput() (and textinput()) instead; second, an aesthetic goal should be to have the turtle move as little as possible to achieve your result, even if that requires more, smarter code. Watch the difference in how this solution draws the picture as opposed to the other:
from turtle import Screen, Turtle
# Ask for user input
DEFAULT_COUNT = 3
screen = Screen()
answer = screen.numinput('Request', 'number of circles(2-6)?', default=DEFAULT_COUNT, minval=2, maxval=6)
if answer is None:
answer = DEFAULT_COUNT
else:
answer = int(answer) # int for range()
# define turtle and set position of turtle
turtle = Turtle()
turtle.speed('fast') # because I have little patience
turtle.penup()
turtle.setpos(-200, -200)
direction = 1
# draw appropriate number of circles using nested loops
for row in range(answer - 1, -1, -1): # loop backward to use last iteration as a flag
for column in range(answer - 1, -1, -1):
turtle.pendown()
turtle.circle(30 * direction)
turtle.penup()
if column:
turtle.forward(60) # not done final time
if row: # every time but the last
turtle.left(90 * direction) # turn +/-90 degrees
turtle.forward(60) # forward the length of one diameter
turtle.left(90 * direction) # turn +/-90 degrees
direction *= -1 # reverse our sense of direction
turtle.hideturtle()
screen.exitonclick()