scikit-learn

scikit-learn is an open source machine learning library featuring classification, regression, clustering, dimensionality reduction, model selection and preprocessing. It has tools for data mining and data analysis, and is built on NumPy, SciPy, and matplotlib.

As per official website, it features:

• Classification : Identifying to which category an object belongs to
• Regression : Predicting a continuous-valued attribute associated with an object
• Clustering : Automatic grouping of similar objects into sets
• Dimensionality reduction : Reducing the number of random variables to consider
• Model selection : Comparing, validating and choosing parameters and models
• Preprocessing : Feature extraction and normalization

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