pandas.DataFrame.getitem¶

Get data from a DataFrame by indexer.

Limitations¶

Supported key can be one of the following:

String literal, e.g. df['A']
A slice, e.g. df[2:5]
A tuple of string, e.g. df[('A', 'B')]
An array of booleans, e.g. df[True,False]
A series of booleans, e.g. df(series([True,False]))

Supported getting a column through getting attribute.

Examples¶

Getting Pandas DataFrame column through getting attribute.¶

import pandas as pd
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})

    return df.C


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem_attr.py
  2
  3
  4
  5
  6
Name: C, dtype: int64

Getting Pandas DataFrame column where key is a string.¶

import pandas as pd
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})

    return df['A']


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem.py
  0
  1
  2
  3
  4
Name: A, dtype: int64

Getting slice of Pandas DataFrame.¶

import pandas as pd
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})

    return df[1:3]


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem_slice.py
   A  B  C
1  1  2  3
2  2  3  4

Getting Pandas DataFrame elements where key is a tuple of strings.¶

import pandas as pd
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})

    return df[('A', 'C')]


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem_tuple.py
   A  C
0  2
1  3
2  4
3  5
4  6

Getting Pandas DataFrame elements where key is an array of booleans.¶

import pandas as pd
import numpy as np
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})
    arr = np.array([False, True, False, False, True])

    return df[arr]


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem_array.py
   A  B  C
1  1  2  3
4  4  5  6

Getting Pandas DataFrame elements where key is series of booleans.¶

import pandas as pd
from numba import njit


@njit
def dataframe_getitem():
    df = pd.DataFrame({'A': [0, 1, 2, 3, 4],
                       'B': [1, 2, 3, 4, 5],
                       'C': [2, 3, 4, 5, 6]})
    val = pd.Series([True, False, True, False, False])

    return df[val]


print(dataframe_getitem())

$ python ./dataframe/getitem/df_getitem_series.py
   A  B  C
0  0  1  2
2  2  3  4

Navigation

pandas.DataFrame.getitem¶

Limitations¶

Examples¶