Selecting Using .loc[]

Unordered Indexing

cereal

	name	mfr	type	calories	...	shelf	weight	cups	rating
0	100% Bran	N	Cold	70	...	3	1.0	0.33	68.402973
1	100% Natural Bran	Q	Cold	120	...	3	1.0	1.00	33.983679
2	All-Bran	K	Cold	70	...	3	1.0	0.33	59.425505
...	...	...	...	...	...	...	...	...	...
74	Wheat Chex	R	Cold	100	...	1	1.0	0.67	49.787445
75	Wheaties	G	Cold	100	...	1	1.0	1.00	51.592193
76	Wheaties Honey Gold	G	Cold	110	...	1	1.0	0.75	36.187559

77 rows × 16 columns

Here we have our trusty cereal dataframe.

What would we do if we wanted to select columns and rows that don’t fall consecutively or if we wanted to rearrange them?

cereal.loc[[13,73,75], ['name', 'type', 'sugars', 'rating']]

	name	type	sugars	rating
13	Clusters	Cold	7	40.400208
73	Trix	Cold	12	27.753301
75	Wheaties	Cold	3	51.592193

cereal.loc[[75, 73, 13], ['name', 'type', 'rating', 'sugars']]

	name	type	rating	sugars
75	Wheaties	Cold	51.592193	3
73	Trix	Cold	27.753301	12
13	Clusters	Cold	40.400208	7

Let’s say we want only the rows labelled:

• Clusters (13)
• Trix (73), and
• Wheaties (75)

And the columns:

• name
• type
• sugars, and
• rating

How would we obtain them?

We need to specify each column and row label that we want between square brackets [], that follow .loc[] and we separate the items that we list in the square brackets with commas.

What if we wanted the rows to be in the order Wheaties (75), Trix (73) and Clusters (13) and columns in the order name, type, rating and sugars.

How would we obtain that?

We would just have to rearranging the order in which we list our rows and columns.

Let’s apply what we learned!