# Python: 4 Ways to Round a Number

## Using the round() function

`round()` is a built-in function of Python that provides a simple and straightforward way to round a number to a given precision in decimal digits.

Example:

``````number = 1.23456

# Round to 3 decimal places
rounded_number = round(number, 3)
print(rounded_number)

# Round to 2 decimal places
rounded_number = round(number, 2)
print(rounded_number)``````

Output:

``````1.235
1.23``````

## Using the math.floor() and math.ceil() functions

Example:

``````import math

number = 1.55677777789

# Round up to the nearest integer
rounded_up = math.ceil(number)
print(rounded_up)

# Round down to the nearest integer
rounded_down = math.floor(number)
print(rounded_down)``````

Output:

``````2
1``````

## Using the format() function

You can round a floating point number by using the `format()` function like so:

``````number = 3.14159

# Format to 4 decimal places
# The result is a string
rounded_number_1 = format(number, ".4f")
# Convert to float
rounded_number_1 = float(rounded_number_1)
print(rounded_number_1)

# Format to 2 decimal places
# The result is a string
rounded_number_2 = format(number, ".2f")
# Convert to float
rounded_number_2 = float(rounded_number_2)
print(rounded_number_2)``````

Output:

``````3.1416
3.14``````

## Using the decimal module

The `quantize()` method returns a value equal to the first operand after rounding and having the exponent of the second operand. You can make use of it for the purpose.

Code example:

``````from decimal import Decimal

number = 3.45678933333333

decimal_number = Decimal(number)
rounded_number = decimal_number.quantize(Decimal("0.00"))
print(rounded_number) ``````

Output:

``3.46``

The type of the output is `decimal`. You can convert it to a float by using the `float()` function:

``rounded_number_float = float(rounded_number)``