Orderby
Sorting in Pandas
- Pandas comes with a function sort_values() which sorts the data.
- sort_values() can sort the data frame in both ascending and descending order.
Syntax of sort_values():
DataFrame.sort_values(by, axis=0, ascending=True, inplace=False, kind='quicksort', na_position='last', ignore_index=False, key=None)
Parameters:
-
by: str or list of str
-
axis : {0 or ‘index’, 1 or ‘columns’}, default 0
-
ascending: bool or list of bool, default True
-
in_place: bool, default False
-
kind{‘quicksort’, ‘mergesort’, ‘heapsort’, ‘stable’}, default ‘quicksort’
Choice of sorting algorithm. See also NumPy.sort() for more information. mergesort and stable are the only stable algorithms. For DataFrames, this option is only applied when sorting on a single column or label. -
na_position : {‘first’, ‘last’}, default ‘last’
Puts NaNs at the beginning if first; last puts NaNs at the end. -
ignore_index: bool, default False
Examples:
Sorting the given dataframe in Ascending Order:
import pandas as pd
# creating and initializing a nested list
data = [['The Matrix', 1999], ['Monster''s Inc', 2001], ['Call me by your name', 2017], ['Star Wars Episode-1', 1999], ['Star Wars Episode-2', 2003], ['Star Wars Episode-3', 2005], ['Love Rosie', 2014], ['Perfect Sence', 2011]]
# creating a pandas dataframe
df = pd.DataFrame(data,columns=['Movies','Year'])
print(df)
print('------------------------------------------')
# Sorting by column 'Movies'
sf = df.sort_values('Movies')
print(sf)
print('------------------------------------------')
# Sorting by year
sf1 = df.sort_values('Year')
print(sf1)
Output:
Movies Year
0 The Matrix 1999
1 Monsters Inc 2001
2 Call me by your name 2017
3 Star Wars Episode-1 1999
4 Star Wars Episode-2 2003
5 Star Wars Episode-3 2005
6 Love Rosie 2014
7 Perfect Sence 2011
------------------------------------------
Movies Year
2 Call me by your name 2017
6 Love Rosie 2014
1 Monsters Inc 2001
7 Perfect Sence 2011
3 Star Wars Episode-1 1999
4 Star Wars Episode-2 2003
5 Star Wars Episode-3 2005
0 The Matrix 1999
------------------------------------------
Movies Year
0 The Matrix 1999
3 Star Wars Episode-1 1999
1 Monsters Inc 2001
4 Star Wars Episode-2 2003
5 Star Wars Episode-3 2005
7 Perfect Sence 2011
6 Love Rosie 2014
2 Call me by your name 2017
Sorting in descending order:
sf1 = df.sort_values('Year',ascending=False)
print(sf1)
Output:
Movies Year
2 Call me by your name 2017
6 Love Rosie 2014
7 Perfect Sence 2011
5 Star Wars Episode-3 2005
4 Star Wars Episode-2 2003
1 Monsters Inc 2001
0 The Matrix 1999
3 Star Wars Episode-1 1999
