remove zeros at the end of a number

[Frankduc]

Hello,

I am trying to remove the .0000 in the result of my window for variable carres and cubes.

I tried truncate, int, round but nothing helps.

from tkinter import *
import math

def afficher():

    nbs = range(20,41)

    for n in nbs:
     carres = n**2
     cubes = n**3

     resultat.insert(INSERT, str(n) + '\t' + '%0.4f' % round(carres)+ '\t' + '%0.4f' % cubes + '\n')


fen1 = Tk()
fen1.title('Afficher les cubes et carrés')

resultat = Text(fen1)
resultat.config(width=40, height= 50)
resultat.insert(INSERT, 'Nombres\tCarrés\tCubes\n============================\n')
resultat.grid(row =1, column = 0, columnspan = 2)

bouton1 = Button(fen1, text = "Afficher", command = afficher)
bouton1.grid(row = 1, column = 0)

bouton2 = Button(fen1, text = "Quitter", command = fen1.destroy)
bouton2.grid(row = 1, column = 1)

fen1.mainloop()

Output:
20 	400.0000	8000.0000
21  	441.0000	9261.0000
22  	484.0000	10648.0000
23 	529.0000	12167.0000
24	    576.0000	13824.0000
25	   625.0000	15625.0000
26	   676.0000	17576.0000
27	   729.0000	19683.0000
28	   784.0000	21952.0000
29  	841.0000	24389.0000

Any pointers?

Thank you

[deanhystad]

That's funny. You are adding the four decimal places when you set the format to '%0.4f'. They wouldn't be there normally since carres and cubes are both ints. If you want to pad the value out to 4 spaces use "%4d".

But you should not use this horrible way of building formatted strings. Use f' strings instead

If you just want to format the results for printing.

import math
print(f"{math.pi}, 4 decimal places {math.pi:.4f}  No decimal places and padded to 5 spaces {math.pi:5.0f}")

Output:
3.141592653589793, 4 decimal places 3.1416  No decimal places and padded to 5 spaces     3

[Frankduc]

Do you need to put the f in front of each variable?

resultat.insert(INSERT, f'{str(n):.0f}' + '\t' + f'{carres:.0f}' + '\t' + f'{cubes:.0f}' + '\n'')

[snippsat]

Change this line to.

resultat.insert(INSERT, str(n) + '\t' + '%d' % round(carres)+ '\t' + '%0.4f' % cubes + '\n')
# To
resultat.insert(tk.INSERT, f"{n}\t{carres}\t{cubes}\n")

So don't use old string formatting(%) learn f-string,also as shown over.
Also don't use * in import is never ok,even if many GUI tutorials do this.
Try to keep 4-space indentation in all code,so to make these changes it will be like this.

import tkinter as tk
import math

def afficher():
    nbs = range(20, 41)
    for n in nbs:
        carres = n**2
        cubes = n**3
        resultat.insert(tk.INSERT, f"{n}\t{carres}\t{cubes}\n")

fen1 = tk.Tk()
fen1.title("Afficher les cubes et carrés")
resultat = tk.Text(fen1)
resultat.config(width=40, height=50)
resultat.insert(tk.INSERT,"Nombres\tCarrés\tCubes\n============================\n",)
resultat.grid(row=1, column=0, columnspan=2)
bouton1 = tk.Button(fen1, text="Afficher", command=afficher)
bouton1.grid(row=1, column=0)
bouton2 = tk.Button(fen1, text="Quitter", command=fen1.destroy)
bouton2.grid(row=1, column=1)
fen1.geometry('300x450')
fen1.mainloop()

[deanhystad]

You do not want to do this:

resultat.insert(INSERT, f'{str(n):.0f}' + '\t' + f'{carres:.0f}' + '\t' + f'{cubes:.0f}' + '\n'')

First off carres and cubes don't have any decimal places, so using ".0f" is not needed to hide the decimal part.

resultat.insert(INSERT, f'{n}' + '\t' + f'{carres}' + '\t' + f'{cubes}' + '\n')

Second, let the f'string do all the formatting. Don't make little pieces and concatenate.

resultat.insert(INSERT, f"{n}\t{carres}\t{cubes}\n")

To prevent ragged columns you probably want to pad the numbers to the same width.

resultat.insert(INSERT, f"{n:2}\t{carres:4}\t{cubes:4}\n")

[Frankduc]

Wow amazing!
That is not in the book. I was following the books teacher.
I didn't put that *, pycharm impose it to me. I just started using it. But i dont like it at all. Its heavy and not user friendly.

Thank you snipp

[deanhystad]

pycharm does not "impose" wildcard imports. It might suggest such a thing, but you can type whatever you please.

Your book is probably too old. f'string formatting was introduced in Python 3.6. You should not rely on any book as the single source of information, and you should not be relying on this forum as your #2 source. After reading about something in you book, google it and see what others have to say about the topic. Look for examples of how a new language feature is used. Maybe do a tutorial.

[Frankduc]

Book is dated 2020. I check on stackoverflow and other sites but info are sometimes contradictory. I use the forum as another source of info. But i am not disappointed, people are nice here, give good and fast info. Maybe not perfect but most of the time reliable. I wouldn't say impose but everytime i use import math or any other module it put automatically a * next to it. I can delete it, true, but its coming back.