Python Forum

I am writing a program to change the given data type.
Here is my code:

a = input("Type the data which you would like to convert: ")
dtype = input("Type the data type which you would like to convert it to: ").lower()
if dtype == "integer" or dtype == "int":
	a = int(a)
	print(f"The data converted to {dtype}: {a}")

elif dtype == "boolean" or dtype == "bool":
	a = bool(a)
	print(f"The data converted to {dtype}: {a}")

elif dtype == "floating" or dtype == "float":
	a = float(a)
	print(f"The data converted to {dtype}: {a}")

elif dtype == "string" or dtype == "str":
	a = str(a)
	print(f"The data converted to {dtype}: {a}")

elif dtype == "complex":
	a = complex(a)
	print(f"The data converted to {dtype}: {a}")

else:
	print("Invalid Input")

print(type(a))

This is the error I get when I try to convert float to integer:

Error:
  File "grp_tasks.py", line 25, in <module>
    a = int(a)
ValueError: invalid literal for int() with base 10: '12.5'

Also when I input "0" and try to convert it to boolean. It shows up as True

Output:
Type the data which you would like to convert: 0
Type the data type which you would like to convert it to: boolean
The data converted to boolean: True

What is wrong with my code?

PS. Changing line 4 to:

a = int(round(a))

solves the error

input() returns a string. So dtype is always a string. Your error results from trying to convert a string with a decimal to int which it cannot do (at least as a string). You would either need to convert it to a float first, or parse out the decimal and after.

>>> int('12.5')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: '12.5'
>>> int(12.5)
12

Any object that contains data is considered True, and if it is empty, is False. And string is just another object.

>>> a = ''
>>> bool(a)
False
>>> b = '0'
>>> bool(b)
True
>>> 

You would first have to convert the string '0' to a int 0 to be considered False.

>>> bool(int(b))
False

(Jun-27-2019, 12:43 PM)metulburr Wrote: [ -> ]input() returns a string. So dtype is always a string. Your error results from trying to convert a string with a decimal to int which it cannot do (at least as a string). You would either need to convert it to a float first, or parse out the decimal and after.

>>> int('12.5')
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: invalid literal for int() with base 10: '12.5'
>>> int(12.5)
12

Any object that contains data is considered True, and if it is empty, is False. And string is just another object.

>>> a = ''
>>> bool(a)
False
>>> b = '0'
>>> bool(b)
True
>>> 

You would first have to convert the string '0' to a int 0 to be considered False.

>>> bool(int(b))
False

Thanks a lot for the explanation!