Python Scikit-learn: K Nearest Neighbors - Convert Species columns in a numerical column of the iris dataframe

Last update on August 19 2022 21:50:29 (UTC/GMT +8 hours)

Python Machine learning K Nearest Neighbors: Exercise-3 with Solution

Write a Python program using Scikit-learn to convert Species columns in a numerical column of the iris dataframe. To encode this data map convert each value to a number. e.g. Iris-setosa:0, Iris-versicolor:1, and Iris-virginica:2. Now print the iris dataset into 80% train data and 20% test data. Out of total 150 records, the training set will contain 120 records and the test set contains 30 of those records. Print both datasets.

Sample Solution:

Python Code:

import pandas as pd
from sklearn.model_selection import train_test_split
iris = pd.read_csv("iris.csv")
# Import LabelEncoder
from sklearn import preprocessing
#creating labelEncoder
le = preprocessing.LabelEncoder()
# Converting string labels into numbers.
iris.Species = le.fit_transform(iris.Species)
#Drop id column
iris = iris.drop('Id',axis=1)
X = iris.iloc[:, :-1].values
y = iris.iloc[:, 4].values
#Split arrays or matrices into random train and test subsets
X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.20)
print("\n80% train data:")
print(X_train)
print(y_train)
print("\n20% test data:")
print(X_test)
print(y_test)

Sample Output:

80% train data:
[[5.7 2.9 4.2 1.3]
 [7.1 3.  5.9 2.1]
 [5.  3.3 1.4 0.2]
 [4.6 3.4 1.4 0.3]
 [5.4 3.4 1.5 0.4]
 [5.7 3.8 1.7 0.3]
 [5.7 3.  4.2 1.2]
 [6.4 2.8 5.6 2.1]
 [5.8 2.7 3.9 1.2]
 [4.5 2.3 1.3 0.3]
 [4.9 2.5 4.5 1.7]
 [6.1 3.  4.6 1.4]
 [6.2 3.4 5.4 2.3]
 [4.9 2.4 3.3 1. ]
 [5.4 3.  4.5 1.5]
 [7.4 2.8 6.1 1.9]
 [6.4 3.1 5.5 1.8]
 [5.3 3.7 1.5 0.2]
 [5.6 2.8 4.9 2. ]
 [6.7 3.3 5.7 2.1]
 [6.3 2.5 5.  1.9]
 [4.9 3.  1.4 0.2]
 [5.2 2.7 3.9 1.4]
 [5.8 2.8 5.1 2.4]
 [5.  3.  1.6 0.2]
 [6.  3.  4.8 1.8]
 [5.9 3.  4.2 1.5]
 [4.8 3.  1.4 0.1]
 [4.8 3.1 1.6 0.2]
 [5.1 3.3 1.7 0.5]
 [7.9 3.8 6.4 2. ]
 [5.7 2.8 4.5 1.3]
 [6.6 3.  4.4 1.4]
 [6.2 2.2 4.5 1.5]
 [6.5 3.  5.8 2.2]
 [4.3 3.  1.1 0.1]
 [6.  2.2 4.  1. ]
 [5.1 3.8 1.9 0.4]
 [6.1 3.  4.9 1.8]
 [5.1 3.8 1.5 0.3]
 [5.  3.6 1.4 0.2]
 [6.  3.4 4.5 1.6]
 [5.  3.5 1.3 0.3]
 [5.7 2.8 4.1 1.3]
 [5.7 2.6 3.5 1. ]
 [6.4 2.8 5.6 2.2]
 [4.7 3.2 1.3 0.2]
 [5.1 3.8 1.6 0.2]
 [6.3 2.7 4.9 1.8]
 [6.9 3.1 5.1 2.3]
 [5.  2.  3.5 1. ]
 [5.4 3.4 1.7 0.2]
 [5.9 3.2 4.8 1.8]
 [6.5 3.  5.2 2. ]
 [6.3 2.3 4.4 1.3]
 [5.1 3.5 1.4 0.3]
 [6.7 3.  5.  1.7]
 [5.4 3.7 1.5 0.2]
 [5.8 2.7 5.1 1.9]
 [5.7 2.5 5.  2. ]
 [5.2 4.1 1.5 0.1]
 [6.9 3.1 5.4 2.1]
 [5.8 2.7 4.1 1. ]
 [6.4 3.2 5.3 2.3]
 [4.6 3.2 1.4 0.2]
 [5.1 2.5 3.  1.1]
 [6.7 3.1 5.6 2.4]
 [5.6 2.9 3.6 1.3]
 [6.3 3.4 5.6 2.4]
 [5.8 2.6 4.  1.2]
 [6.3 2.9 5.6 1.8]
 [5.2 3.5 1.5 0.2]
 [6.1 2.8 4.7 1.2]
 [6.9 3.2 5.7 2.3]
 [5.  3.4 1.5 0.2]
 [5.5 2.4 3.7 1. ]
 [6.  2.9 4.5 1.5]
 [4.9 3.1 1.5 0.1]
 [5.5 2.3 4.  1.3]
 [6.9 3.1 4.9 1.5]
 [7.7 2.6 6.9 2.3]
 [5.8 2.7 5.1 1.9]
 [6.7 3.  5.2 2.3]
 [5.  3.2 1.2 0.2]
 [6.7 3.1 4.7 1.5]
 [5.1 3.7 1.5 0.4]
 [7.2 3.6 6.1 2.5]
 [5.6 3.  4.1 1.3]
 [7.7 3.8 6.7 2.2]
 [5.5 2.5 4.  1.3]
 [4.7 3.2 1.6 0.2]
 [6.  2.7 5.1 1.6]
 [5.6 3.  4.5 1.5]
 [5.5 2.6 4.4 1.2]
 [6.  2.2 5.  1.5]
 [6.2 2.9 4.3 1.3]
 [5.4 3.9 1.3 0.4]
 [6.4 3.2 4.5 1.5]
 [6.5 3.  5.5 1.8]
 [5.5 3.5 1.3 0.2]
 [6.7 3.3 5.7 2.5]
 [6.7 3.1 4.4 1.4]
 [6.3 2.5 4.9 1.5]
 [5.  3.5 1.6 0.6]
 [6.3 2.8 5.1 1.5]
 [5.  2.3 3.3 1. ]
 [4.9 3.1 1.5 0.1]
 [7.2 3.  5.8 1.6]
 [7.2 3.2 6.  1.8]
 [6.4 2.9 4.3 1.3]
 [5.6 2.7 4.2 1.3]
 [5.2 3.4 1.4 0.2]
 [6.5 3.2 5.1 2. ]
 [6.6 2.9 4.6 1.3]
 [7.  3.2 4.7 1.4]
 [5.9 3.  5.1 1.8]
 [4.6 3.1 1.5 0.2]
 [4.6 3.6 1.  0.2]
 [5.4 3.9 1.7 0.4]
 [4.4 2.9 1.4 0.2]]
[1 2 0 0 0 0 1 2 1 0 2 1 2 1 1 2 2 0 2 2 2 0 1 2 0 2 1 0 0 0 2 1 1 1 2 0 1
 0 2 0 0 1 0 1 1 2 0 0 2 2 1 0 1 2 1 0 1 0 2 2 0 2 1 2 0 1 2 1 2 1 2 0 1 2
 0 1 1 0 1 1 2 2 2 0 1 0 2 1 2 1 0 1 1 1 2 1 0 1 2 0 2 1 1 0 2 1 0 2 2 1 1
 0 2 1 1 2 0 0 0 0]

20% test data:
[[4.4 3.  1.3 0.2]
 [6.2 2.8 4.8 1.8]
 [6.1 2.6 5.6 1.4]
 [5.  3.4 1.6 0.4]
 [6.8 3.2 5.9 2.3]
 [4.8 3.  1.4 0.3]
 [7.7 3.  6.1 2.3]
 [6.8 2.8 4.8 1.4]
 [6.3 3.3 6.  2.5]
 [6.1 2.9 4.7 1.4]
 [6.7 2.5 5.8 1.8]
 [7.6 3.  6.6 2.1]
 [6.1 2.8 4.  1.3]
 [5.1 3.4 1.5 0.2]
 [6.8 3.  5.5 2.1]
 [6.4 2.7 5.3 1.9]
 [5.7 4.4 1.5 0.4]
 [6.3 3.3 4.7 1.6]
 [4.8 3.4 1.9 0.2]
 [4.9 3.1 1.5 0.1]
 [4.4 3.2 1.3 0.2]
 [5.1 3.5 1.4 0.2]
 [5.6 2.5 3.9 1.1]
 [4.8 3.4 1.6 0.2]
 [7.7 2.8 6.7 2. ]
 [5.5 2.4 3.8 1.1]
 [6.5 2.8 4.6 1.5]
 [7.3 2.9 6.3 1.8]
 [5.8 4.  1.2 0.2]
 [5.5 4.2 1.4 0.2]]
[0 2 2 0 2 0 2 1 2 1 2 2 1 0 2 2 0 1 0 0 0 0 1 0 2 1 1 2 0 0]

Python Code Editor:

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Previous: Write a Python program using Scikit-learn to split the iris dataset into 70% train data and 30% test data. Out of total 150 records, the training set will contain 120 records and the test set contains 30 of those records. Print both datasets.
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