HomeSearch | ## Python Round Up and Down (Math Round)Call round to round numbers up and down. With math.ceil a number is rounded up. | |

## Round.A number has a fractional part. For example 1.45 is between and 1 and 2 and we want to round it. With round() we can round it to 1 or 1.5. | ||

## To always round up,please consider the math.ceil method. And to always round down, use math.floor. But to retain a fractional part, round() is helpful. | ||

## Round example.This receives one or two arguments. The second argument is optional. Round() returns a rounded number—we use it in an assignment.
| Python program that uses round
number = 1.23456
# Use round built-in.
# ... This rounds up or down depending on the last digit.
print(round(number))
print(round(number, 0))
print(round(number, 1))
print(round(number, 2))
print(round(number, 3))
Output
1 0 digits
1.0 0 digits
1.2 1 digit
1.23 2 digits
1.235 3 digits, last one rounded up to 5 | |

## Round up, down.Let us consider this program. We use math.ceil to always round up to the nearest integer. Round() cannot do this—it will round up or down depending on the fractional value.
| Python program that rounds up, down
import math
number = 1.1
# Use math.ceil to round up.
result = math.ceil(number)
print(result)
# The round method will round down because 1.1 is less than 1.5.
print(round(number))
Output
2
1 | |

## Syntax notes.There is no math.round function in Python 3. Trying to invoke math.round will lead to an AttributeError. Please just use round().Error | Error message, math.round:
Traceback (most recent call last):
File "C:\programs\file.py", line 6, in <module>
number = math.round(1.1)
AttributeError: 'module' object has no attribute 'round' | |

## Math notes.Additional methods in Python can transform numbers as needed. The abs method provides absolute values. Built-in math methods make programs simpler.Math | ||

## A review.With round() in Python we gain a way to reduce the number of digits past the decimal place. Round increases or decreases a number based on the last digit. | ||

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