Размер чисел в питоне

Размер чисел в питоне

Last updated: Feb 18, 2023
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# Table of Contents

# Get the length of an Integer in Python

To get the length of an integer in Python:

1. Use the str() class to convert the integer to a string.
2. Pass the string to the len() function, e.g. len(my_str) .
3. The len() function will return the length of the string.

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my_int = 1234 my_str = str(my_int) print(len(my_str)) # 👉️ 4 

The len() function returns the length (the number of items) of an object.

The argument the function takes may be a sequence (a string, tuple, list, range or bytes) or a collection (a dictionary, set, or frozen set).

This is why we had to convert the integer to a string — we can’t pass an integer to the len() function as integers are not a sequence or a collection.

# Handling possibly negative numbers

If you need to handle a scenario where the number is negative, subtract 1 from the result.

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my_int = -1234 if my_int  0: result = len(str(my_int)) - 1 else: result = len(str(my_int)) print(result) # 👉️ 4 

We check if the integer is less than 0 , and if it is, we subtract 1 from its length to account for the minus — sign.

# Get the length of an integer without conversion to string

You can use the math.log10() method to get the length of an integer without converting it to a string.

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import math def get_integer_length(integer): return int(math.log10(integer)) + 1 print(get_integer_length(100)) # 👉️ 3 print(get_integer_length(12345)) # 👉️ 5 

The math.log10 method returns the base-10 logarithm of the supplied number.

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import math print(math.log10(100)) # 2.0 print(math.log10(12345)) # 4.091491094267951 

The log10() method cannot be invoked with a negative number or 10 , otherwise, and error is raised.

# Handling negative numbers when using math.log10

If you need to handle negative numbers, make sure to only call the math.log10() method if the supplied number is greater than 0 .

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import math def get_integer_length(integer): if integer > 0: return int(math.log10(integer)) + 1 elif integer == 0: return 1 else: return int(math.log10(-integer)) + 2 print(get_integer_length(100)) # 3 print(get_integer_length(12345)) # 5 print(get_integer_length(-1234)) # 5 print(get_integer_length(0)) # 1 

If the given number is equal to 0 , we return that it has a length of 1 .

If the number is positive, we use the math.log10 method to get its length.

If the number is negative, we prefix it with a minus — sign to convert it to a positive number before calling math.log10 .

If you don’t want to count the minus — sign in the result, add 1 to the result of calling math.log10() if the number is negative.

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import math def get_integer_length(integer): if integer > 0: return int(math.log10(integer)) + 1 elif integer == 0: return 1 else: return int(math.log10(-integer)) + 1 # 👈️ add 1 print(get_integer_length(-12)) # 2 print(get_integer_length(-1234)) # 4 

The function above doesn’t include the minus — sign in the length of negative numbers.

# If you consider 0 to have a length of 0

If your application considers the number 0 to have a length of 0 , add an elif statement to check for 0 .

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my_int = 0 if my_int  0: result = len(str(my_int)) - 1 elif my_int == 0: result = 0 else: result = len(str(my_int)) print(result) # 👉️ 0 

The if statement checks if the number is less than 0 , and if it is, it subtracts 1 .

The elif statement checks if the number is equal to 0 , and if it is, we assign 0 to the result variable.

If the else statement runs, the integer is positive, so we can convert it to a string and pass the string to the len() function.

# Get the length of an Integer using a formatted string literal

You can also use a formatted string literal to get the length of an integer.

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my_int = 123 result = len(f'my_int>') print(result) # 👉️ 3 

Formatted string literals (f-strings) let us include expressions inside of a string by prefixing the string with f .

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my_str = 'is subscribed:' my_bool = True result = f'my_str> my_bool>' print(result) # 👉️ is subscribed: True 

Make sure to wrap expressions in curly braces — .

# Get the length of a Float in Python

If you need to get the length of a float:

1. Use the str() class to convert the float to a string.
2. Pass the string to the len() function, e.g. len(result) .
3. The len() function will return the length of the string.

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my_float = 3.14 my_str = str(my_float) print(len(my_str)) # 👉️ 4 without_counting_decimal = len(my_str) - 1 print(without_counting_decimal) # 👉️ 3 

The len() function returns the length (the number of items) of an object.

The argument the function takes may be a sequence (a string, tuple, list, range or bytes) or a collection (a dictionary, set, or frozen set).

This is why we had to convert the floating-point number to a string — we can’t pass a float to the len() function as floats are not a sequence or a collection.

# Not counting the decimal

If you don’t want to count the decimal, either subtract 1 from the result or replace it with an empty string.

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my_float = 3.14 my_str = str(my_float) print(len(my_str)) # 👉️ 4 no_decimal_1 = len(my_str) - 1 print(no_decimal_1) # 👉️ 3 no_decimal_2 = len(my_str.replace('.', '')) print(no_decimal_2) # 👉️ 3 

We used the str.replace() method to remove the decimal from the string by replacing it with an empty string.

# Handling negative floating-point numbers

If you need to handle a scenario where the number is negative, subtract 1 from the result.

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my_float = 3.14 if my_float  0: result = len(str(my_float)) - 1 else: result = len(str(my_float)) print(result) # 👉️ 4 

We check if the float is less than 0 , and if it is, we subtract 1 from its length to account for the minus — sign.

# Using a formatted string literal to get the length of a float

You can also use a formatted string literal to get the length of a float.

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my_float = 3.14 result = len(f'my_float>') print(result) # 👉️ 4 

Formatted string literals (f-strings) let us include expressions inside of a string by prefixing the string with f .

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my_str = 'is subscribed:' my_bool = True result = f'my_str> my_bool>' print(result) # 👉️ is subscribed: True 

Make sure to wrap expressions in curly braces — .

# Additional Resources

You can learn more about the related topics by checking out the following tutorials:

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