How Do I Correctly Implement A Bubble Sort Algorithm In Python Tkinter?

I am making a series of articles about sorting algorithms, and the first part is about bubble sorting, I have the GUI elements in place, but the sorting algorithm itself is not wor

Solution 1:

The biggest problem is that inside sort_two you have if

if y2 > y1:
    canvas.move(pos_0, x_10-x_00, 0)
    canvas.move(pos_1, x_01-x_11, 0)

which replaces elements only if y2 > y1

but after sort_two() you use barList

sort_two(pos_1, pos_2)
barList[rd1], barList[rd2] = barList[rd2], barList[rd1]

which always replaces elements on list.

And this way you have wrong results on screen.

You could return True/False from sort_two() to control when to change elements on barList

if y2 > y1:
    canvas.move(pos_0, x_10-x_00, 0)
    canvas.move(pos_1, x_01-x_11, 0)
    return True
else:
    return False

and

ifsort_two(pos_1, pos_2):
    barList[rd1], barList[rd2] = barList[rd2], barList[rd1]

---

Here finall code

I use simple calculation for replacing elements on canvas

x1, _, _, _ = canvas.coords(pos_0)
x2, _, _, _ = canvas.coords(pos_1)

diff = x1 - x2

canvas.move(pos_0, -diff, 0)
canvas.move(pos_1, +diff, 0)

I also removed

else:
    break

which stop animation after every replace and it needs to click button sort again and again - and I use

    window.update()
    time.sleep(0.1)

so it displays animation (slowly) to the end of sorting and I don't have to click button sort

import tkinter as tk
import random
import time

defswap_two_pos(pos_0, pos_1):
    """This does the graphical swapping of the rectangles on the canvas
    by moving one rectangle to the location of the other, and vice versa
    """    
    
    x1, _, _, _ = canvas.coords(pos_0)
    x2, _, _, _ = canvas.coords(pos_1)
    
    diff = x1 - x2

    canvas.move(pos_0, -diff, 0)
    canvas.move(pos_1, +diff, 0)

defsort_two(pos_0, pos_1):
    x1, y1, _, _ = canvas.coords(pos_0)
    x2, y2, _, _ = canvas.coords(pos_1)

    diff = x1 - x2

    # moves each rectangle to the x position of the other; y remains unchangedif y2 > y1:
        canvas.move(pos_0, -diff, 0)
        canvas.move(pos_1, +diff, 0)
        returnTrueelse:
        returnFalsedefrand_sort():
    for i inrange(50000):
        rd1 = random.randint(0, 58)
        rd2 = random.randint(0, 58)
        pos_1 = barList[rd1]
        pos_2 = barList[rd2]
        if sort_two(pos_1, pos_2):
            barList[rd1], barList[rd2] = barList[rd2], barList[rd1]

defsort ():
    n = len(barList)
  
    # Traverse through all array elements for i inrange(n): 
  
        # Last i elements are already in place for j inrange(0, n-i-1):
            if sort_two(barList[j], barList[j+1]):
                barList[j], barList[j+1] = barList[j+1], barList[j]
            
        window.update()
        time.sleep(0.1)
        
        
defrandom_swap():
    """Not a sort yet, but you have the bare bones operations
    so the swap is executed
    """for i inrange(500):
        rd1 = random.randint(0, 58)
        rd2 = random.randint(0, 58)
        pos_0 = barList[rd1]
        pos_1 = barList[rd2]
        
        swap_two_pos(pos_0, pos_1)
        # it is necessary to swap the values in the list too
        barList[rd1], barList[rd2] = barList[rd2], barList[rd1]

window = tk.Tk()
window.title('Sorting')
window.geometry('600x400')

# button to command the swap
tk.Button(window, text='swap', command=random_swap).pack()
tk.Button(window, text='sort', command=sort).pack()

xstart = 5
xend = 15
canvas = tk.Canvas(window, width='900', height='900')
canvas.pack()
barList = []
lengthList = []
Y = 5for x inrange(1,60):
    bar = canvas.create_rectangle(xstart, Y, xend, 395, fill='red')
    barList.append(bar)
    xstart += 10
    xend += 10
    Y += 5for bar in barList:
    x = canvas.coords(bar)
    length = x[3]-x[1]
    lengthList.append(length)

window.mainloop()