How To Stop Python From Rounding

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Python is a versatile language, but sometimes its default behavior can be a little frustrating – especially when it comes to rounding floating-point numbers. In this blog post, we will explore how to stop Python from rounding and display the precise decimal value that you need.

1. Use the Decimal Module

Python’s decimal module provides a more precise way of dealing with floating-point numbers than the built-in float type. The Decimal type allows you to control the exactness of your calculations, as well as the rounding method used.

To use the Decimal type, you’ll first need to import the decimal module:

import decimal

Now, you can create a Decimal object:

number = decimal.Decimal(‘3.141592653589793238462643383279’)
print(number)

This will output the full value of pi, without rounding:

    3.141592653589793238462643383279

2. Use the f-string Formatting Method

Python 3.6 introduced a new way of formatting strings, called f-strings or formatted string literals. With f-strings, you can specify the number of decimal places you want to display by using the format specifier {value:.nf}, where n is the number of decimal places you want to display:

pi = 3.141592653589793238462643383279
print(f”{pi:.20f}”)

This will output the value of pi with 20 decimal places:

    3.14159265358979311600

3. Use the format() Function

If you’re using Python 3.5 or earlier, you can use the format() function to achieve the same result as f-strings. The syntax is slightly different – you’ll need to use ‘{: .nf}’.format(value):

pi = 3.141592653589793238462643383279
formatted_pi = “{:.20f}”.format(pi)
print(formatted_pi)

Again, this will output the value of pi with 20 decimal places:

    3.14159265358979311600

4. Use the str.format() Method

Another way to format your floating-point numbers is by using the str.format() method. This method is available in both Python 2 and Python 3:

pi = 3.141592653589793238462643383279
formatted_pi = “{:.20f}”.format(pi)
print(formatted_pi)

Just like the previous methods, this will also output the value of pi with 20 decimal places:

    3.14159265358979311600

Conclusion

Now you know four different ways to stop Python from rounding your floating-point numbers. Each of these methods has its own pros and cons, but they all provide more control over number formatting than Python’s default behavior. Choose the method that works best for your needs and enjoy precise calculations in your Python programs!