Pandas: Get the numeric representation of an array by identifying distinct values of a given column of a DataFrame

Last update on May 28 2022 13:07:19 (UTC/GMT +8 hours)

Pandas: DataFrame Exercise-77 with Solution

Write a Pandas program to get the numeric representation of an array by identifying distinct values of a given column of a DataFrame.

Sample Solution :

Python Code :

import pandas as pd
df = pd.DataFrame({
    'Name': ['Alberto Franco','Gino Mcneill','Ryan Parkes', 'Eesha Hinton', 'Gino Mcneill'],
    'Date_Of_Birth ': ['17/05/2002','16/02/1999','25/09/1998','11/05/2002','15/09/1997'],
    'Age': [18.5, 21.2, 22.5, 22, 23]
})
print("Original DataFrame:")
print(df)
label1, unique1 = pd.factorize(df['Name'])
print("\nNumeric representation of an array by identifying distinct values:")
print(label1)
print(unique1)

Sample Output:

Original DataFrame:
             Name Date_Of_Birth    Age
0  Alberto Franco     17/05/2002  18.5
1    Gino Mcneill     16/02/1999  21.2
2     Ryan Parkes     25/09/1998  22.5
3    Eesha Hinton     11/05/2002  22.0
4    Gino Mcneill     15/09/1997  23.0

Numeric representation of an array by identifying distinct values:
[0 1 2 3 1]
Index(['Alberto Franco', 'Gino Mcneill', 'Ryan Parkes', 'Eesha Hinton'], dtype='object')

Python-Pandas Code Editor:

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Python: Tips of the Day

Find current directory and file's directory:

To get the full path to the directory a Python file is contained in, write this in that file:

import os 
dir_path = os.path.dirname(os.path.realpath(__file__))

(Note that the incantation above won't work if you've already used os.chdir() to change your current working directory, since the value of the __file__ constant is relative to the current working directory and is not changed by an os.chdir() call.)

To get the current working directory use

import os
cwd = os.getcwd()

Documentation references for the modules, constants and functions used above:

The os and os.path modules.
The __file__ constant
os.path.realpath(path) (returns "the canonical path of the specified filename, eliminating any symbolic links encountered in the path")
os.path.dirname(path) (returns "the directory name of pathname path")
os.getcwd() (returns "a string representing the current working directory")
os.chdir(path) ("change the current working directory to path")

Ref: https://bit.ly/3fy0R6m