usrbinenv python3 sortinganimation py a minimal sorting algorithm animation sorts a shelf of 10 blocks using insertion sort selection sort and quicksort shelfs are implemented using builtin lists blocks are turtles with shape square but stretched to rectangles by shapesize to exit press space button align blocks by the bottom edge align blocks by the bottom edge usr bin env python3 sorting_animation py a minimal sorting algorithm animation sorts a shelf of 10 blocks using insertion sort selection sort and quicksort shelfs are implemented using builtin lists blocks are turtles with shape square but stretched to rectangles by shapesize to exit press space button square rectangle align blocks by the bottom edge align blocks by the bottom edge range is non inclusive of ending value move pivot to correct position
from turtle import *
import random


class Block(Turtle):

    def __init__(self, size):
        self.size = size
        Turtle.__init__(self, shape="square", visible=False)
        self.pu()
        self.shapesize(size * 1.5, 1.5, 2) 
        self.fillcolor("black")
        self.st()

    def glow(self):
        self.fillcolor("red")

    def unglow(self):
        self.fillcolor("black")

    def __repr__(self):
        return "Block size: {0}".format(self.size)


class Shelf(list):

    def __init__(self, y):
        "create a shelf. y is y-position of first block"
        self.y = y
        self.x = -150

    def push(self, d):
        width, _, _ = d.shapesize()
        
        y_offset = width / 2 * 20
        d.sety(self.y + y_offset)
        d.setx(self.x + 34 * len(self))
        self.append(d)

    def _close_gap_from_i(self, i):
        for b in self[i:]:
            xpos, _ = b.pos()
            b.setx(xpos - 34)

    def _open_gap_from_i(self, i):
        for b in self[i:]:
            xpos, _ = b.pos()
            b.setx(xpos + 34)

    def pop(self, key):
        b = list.pop(self, key)
        b.glow()
        b.sety(200)
        self._close_gap_from_i(key)
        return b

    def insert(self, key, b):
        self._open_gap_from_i(key)
        list.insert(self, key, b)
        b.setx(self.x + 34 * key)
        width, _, _ = b.shapesize()
        
        y_offset = width / 2 * 20
        b.sety(self.y + y_offset)
        b.unglow()

def isort(shelf):
    length = len(shelf)
    for i in range(1, length):
        hole = i
        while hole > 0 and shelf[i].size < shelf[hole - 1].size:
            hole = hole - 1
        shelf.insert(hole, shelf.pop(i))
    return

def ssort(shelf):
    length = len(shelf)
    for j in range(0, length - 1):
        imin = j
        for i in range(j + 1, length):
            if shelf[i].size < shelf[imin].size:
                imin = i
        if imin != j:
            shelf.insert(j, shelf.pop(imin))

def partition(shelf, left, right, pivot_index):
    pivot = shelf[pivot_index]
    shelf.insert(right, shelf.pop(pivot_index))
    store_index = left
    for i in range(left, right): 
        if shelf[i].size < pivot.size:
            shelf.insert(store_index, shelf.pop(i))
            store_index = store_index + 1
    shelf.insert(store_index, shelf.pop(right)) 
    return store_index

def qsort(shelf, left, right):
    if left < right:
        pivot_index = left
        pivot_new_index = partition(shelf, left, right, pivot_index)
        qsort(shelf, left, pivot_new_index - 1)
        qsort(shelf, pivot_new_index + 1, right)

def randomize():
    disable_keys()
    clear()
    target = list(range(10))
    random.shuffle(target)
    for i, t in enumerate(target):
        for j in range(i, len(s)):
            if s[j].size == t + 1:
                s.insert(i, s.pop(j))
    show_text(instructions1)
    show_text(instructions2, line=1)
    enable_keys()

def show_text(text, line=0):
    line = 20 * line
    goto(0,-250 - line)
    write(text, align="center", font=("Courier", 16, "bold"))

def start_ssort():
    disable_keys()
    clear()
    show_text("Selection Sort")
    ssort(s)
    clear()
    show_text(instructions1)
    show_text(instructions2, line=1)
    enable_keys()

def start_isort():
    disable_keys()
    clear()
    show_text("Insertion Sort")
    isort(s)
    clear()
    show_text(instructions1)
    show_text(instructions2, line=1)
    enable_keys()

def start_qsort():
    disable_keys()
    clear()
    show_text("Quicksort")
    qsort(s, 0, len(s) - 1)
    clear()
    show_text(instructions1)
    show_text(instructions2, line=1)
    enable_keys()

def init_shelf():
    global s
    s = Shelf(-200)
    vals = (4, 2, 8, 9, 1, 5, 10, 3, 7, 6)
    for i in vals:
        s.push(Block(i))

def disable_keys():
    onkey(None, "s")
    onkey(None, "i")
    onkey(None, "q")
    onkey(None, "r")

def enable_keys():
    onkey(start_isort, "i")
    onkey(start_ssort, "s")
    onkey(start_qsort, "q")
    onkey(randomize, "r")
    onkey(bye, "space")

def main():
    getscreen().clearscreen()
    ht(); penup()
    init_shelf()
    show_text(instructions1)
    show_text(instructions2, line=1)
    enable_keys()
    listen()
    return "EVENTLOOP"

instructions1 = "press i for insertion sort, s for selection sort, q for quicksort"
instructions2 = "spacebar to quit, r to randomize"

if __name__=="__main__":
    msg = main()
    mainloop()