seperating input number in thousands

[fonzali]

in windows calculator the digits get seperated in thousands as you type in the number , how can it be done in python ? thanks

[Gribouillis]

Do you already have some code for the calculator ? Are you using a GUI toolkit ?

[fonzali]

long time ago I wrote a simple program that adds the amounts of checks and does some analysis on them for my business , it simply asks for the amount of the check and the dates . in Iran due to inflation most of the checks have too many zeros on them and it helps to see them seperated by ',' as we type them in , that was the reason I asked .

[Schol-R-LEA]

I am guessing that you used the built-in float type for this, but given that you are dealing with currency, I would recommend using the decimal module for representing the monetary value instead, to get the best control over the significant decimal places, and applying locale.currency() to format the value as a string. While the links I posted are for the Python 3.4 docs, thhis should apply to Python 2.7 as well.

[snippsat]

Use string formatting

>>> value = 1000000000000
>>> n = "{:,}".format(value)
>>> print(n)
1,000,000,000,000
>>> #Back to float
>>> float(n.translate(None, ','))
1000000000000.0

[fonzali]

thank you guys for your suggestions , but what I am looking for is this : suppose my program asks for the amount on the check , as I am typing , I like to see the numbers being seperated in thousands , in other words looking at snippsat code when I am asked for the value in line one , and I enter the number without ',' I want it to appear like line 4 eg:

>>> amount=int(input('please enter the amount of the check   '))
please enter the amount of the check   1,000,000,000

[fonzali]

by the way @Schol-R-LEA my program reads in the numbers as integers because they all are but just to be complete I will re-write it to your suggestion

[Gribouillis]

You need a GUI to do that, for example a tkinter Entry widget plus supporting code to handle each key stroke and mouse event sent to this widget.

[fonzali]

thanks Gribouillis , that is what I thought too , but looking at snippsat code I got an idea , I can input the numbers using ',' (do I have to declare them as strings ? ) and then inside my code change them to float or int

[Gribouillis]

Yes, you can enter the commas explicitely and parse the input later. For example you can remove every comma before converting to float or int

userdata = input('please enter the amount of the check   ')
userdata = userdata.replace(',', '')
amount = int(userdata)

You can improve this by adding a loop and input validation, for example a valid input matches the regex

r'^\s*\d{1,3}{\,\d{3}}*\s*$'

[fonzali]

thanks Gribouillis , I have enough info to redo my code now . I have to brush up on regex , I have forgotten most of it . thanks again