What is machine learning ?

Supervised learning

Data Representations

Dataset Split


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% matplotlib nbagg
import matplotlib.pyplot as plt
import numpy as np

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from sklearn.datasets import load_digits
digits = load_digits()
digits.keys()

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digits.images.shape

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print(digits.images[0])

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plt.matshow(digits.images[0], cmap=plt.cm.Greys)

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digits.data.shape

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digits.target.shape

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digits.target

Data is always a numpy array (or sparse matrix) of shape (n_samples, n_features)

Splitting the data:


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from sklearn.cross_validation import train_test_split
X_train, X_test, y_train, y_test = train_test_split(digits.data, digits.target)

Exercises

Load the iris dataset from the sklearn.datasets module using the load_iris function. The function returns a dictionary-like object that has the same attributes as digits.

What is the number of classes, features and data points in this dataset? Use a scatterplot to visualize the dataset.

You can look at DESCR attribute to learn more about the dataset.


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# %load solutions/load_iris.py

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