DataScienceAndBigDataAnalytics/Codes/Code-A1 (Data Wrangling-1).md

A1 - Data Wrangling-1

✅ Tested and working as intended.

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Pre-requisites

• Install required libraries: pandas & numpy

pip install pandas numpy

• Save the dataset iris.csv in the same directory as this Jupyter notebook.

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Code blocks

1. Import libraries:

import pandas as pd
import numpy as np

2. Load the dataset from a CSV file into a pandas DataFrame:

df=pd.read_csv('iris.csv')
df.describe() # Print description of DataFrame

3. Print first and last 5 values:

print("First 5 values:\n", df.head())
print ("Last 5 values:\n", df.tail())

4. Print duplicated values:

df.duplicated()

5. Print null values true/false:

df.isnull()

6. Print summary of DataFrame:

df.info()

7. Print shape, i.e. rows + columns:

df.shape

8. Print null (true/false) values in sepal.length column:

df["sepal.length"].isnull()

9. Delete/Drop petal.length column:

y = df.drop(["petal.length"], axis=1) # axis=1 column. For row, axis=0
print(y)

10. In variety column, replace Setosa with 0 and Virginica with 1:

df['variety'].replace(['Setosa', 'Virginica'], [0,1], inplace=True)
print(df)

11. Print sum of NULL values in each column:

df.isnull().sum()

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