python gives me unexpected variable

Question

def check(checked):
    checked = {}
    if checked == float:
        return format(checked, '.2f')
    else:
        checked = "not a float"
        return checked

# convert to float and check

a = input('Enter price for item 1 : ')
a = check(a)

b = input('Enter price for item 2 : ')
c = input('Enter price for item 3 : ')
d = input('Enter price for item 4 : ')
e = input('Enter price for item 5 : ')

print(a)

whenever I use input for a and expect it to change it returns as not a float even when it has a decimal point. I am trying to get a number to a 2 decimal point limit and if it's not a float value to ignore it. I put the else statement to see what's been going wrong I tried using is instead of == but I still get the same result.

Does this answer your question? [Determine the type of an object?](https://stackoverflow.com/questions/2225038/determine-the-type-of-an-object) First of all you reassign your argument by doing `checked = {}`. Then you are comparing it to the **type** `float`. This will always be `False`. Check the link to see how to determine objects' types — Tomerikoo, Jun 16 '20 at 15:21

Rishabh Ankit · Answer 1 · 2020-06-16T15:46:01.420

In python whatever input you take integer,float or any other ,The Input will be of String data type.

Here is the solution of your problem , It will only work if the input is positive value and the input is either float or integer.

Code:

def check(checked):

    if checked.isdigit():
        return checked
    else:
        return format(float(checked), '.2f')

a = input('Enter price for item 1 : ')
print(check(a))

This code will return float value upto 2 decimal places if float value is entered and will leave the number as it is if its not a float value

Tom Harvey · Accepted Answer · 2020-06-16T22:01:43.763

You’re reassigning the checked variable. Don’t do that.

def check(checked):
    if isinstance(checked, float):
        return format(checked, '.2f')
    else:
        return "not a float"

Not sure what you were trying to achieve with checked = {} but all it seemed to be doing was ensuring that checked was always a dictionary, never a float, and never the actual bout value.

To test if something is a float you use isinstance, not == or is

And then reassigning checked to a message which was returned “not a float” is just bad practice.

See the above for a cleaner and (hopefully) working implementation

python gives me unexpected variable

2 Answers2