How To Round Up In Python

Rounding up numbers in Python is a common operation that is necessary in various calculations and data manipulations. In this tutorial, we will explore different ways to round up numbers in Python using various built-in functions and libraries.

Step 1: Using the math.ceil() function

The simplest and most widely used method for rounding up numbers is using the ceil() function from Python’s math library. The ceil() function takes a single argument and returns the smallest integer greater than or equal to that number. Let’s start by importing the math library and using the ceil() function.

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import math
 
number = 4.7
rounded_number = math.ceil(number)

Output:

5

Step 2: Using the decimal library

Another way to round up numbers is by using the Decimal library, which provides a more accurate representation of decimal numbers. To round up a number using the Decimal library, you can use the quantize() function with the rounding option ROUND_UP.

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from decimal import Decimal, ROUND_UP
 
number_decimal = Decimal('4.7')
rounded_number_decimal = number_decimal.quantize(Decimal('1'), rounding=ROUND_UP)

Output:

5

Step 3: Using the numpy library

If you are working with numerical data or arrays, the numpy library is more suited for rounding operations. You can round up numbers using the numpy library by calling the numpy.ceil() function.

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import numpy as np
 
number_np = 4.7
rounded_number_np = np.ceil(number_np)

Output:

5.0

Step 4: Using the pandas library

While working with tabular data structures such as DataFrames or Series, you may need to round up numbers using the pandas library. You can round up all numbers in a DataFrame or Series by calling the apply() function and passing in math.ceil as the argument.

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import pandas as pd
 
data = {'A': [1.2, 2.7, 3.4], 'B': [1.23, 4.75, 6.6]}
df = pd.DataFrame(data)
 
df_rounded = df.apply(lambda x: x.apply(math.ceil))

Output:

   A  B
0  2  2
1  3  5
2  4  7

Full Code:

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import math
from decimal import Decimal, ROUND_UP
import numpy as np
import pandas as pd
 
# Using math.ceil()
number = 4.7
rounded_number = math.ceil(number)
print(rounded_number)
 
# Using Decimal library
number_decimal = Decimal('4.7')
rounded_number_decimal = number_decimal.quantize(Decimal('1'), rounding=ROUND_UP)
print(rounded_number_decimal)
 
# Using numpy
number_np = 4.7
rounded_number_np = np.ceil(number_np)
print(rounded_number_np)
 
# Using pandas
data = {'A': [1.2, 2.7, 3.4], 'B': [1.23, 4.75, 6.6]}
df = pd.DataFrame(data)
 
df_rounded = df.apply(lambda x: x.apply(math.ceil))
print(df_rounded)

Conclusion

In this tutorial, we covered various techniques to round up numbers in Python using built-in functions and libraries like math, Decimal, numpy, and pandas. The method you choose to round up numbers depends on your application requirements and the data structures you are working with.