
Learn principal component analysis (PCA) as an unsupervised, linear method for dimensionality reduction and feature extraction, producing uncorrelated, orthogonal components by maximizing variance through optimized coefficients.
Form PCA as an optimization: maximize z = u^T x by a unit vector u, yielding variance z = u^T C u with C the covariance matrix.
Apply eigenvalues and eigenvectors of the covariance matrix to maximize variance along principal components. Choose top eigenvectors to form the transformation and map X to Z for dimensionality reduction.
Learn to implement principal component analysis from scratch in Python using matrix operations, compute the covariance matrix, extract eigenvectors, and project data onto the first principal component for dimensionality reduction.
Apply principal component analysis on iris dataset using scikit-learn in Python to reduce four features to two components, transforming data and visualizing class separation in a two-dimensional scatter plot.
Apply principal component analysis to the handwritten digits dataset in Python, reducing 64 features to 2 and visualizing the two components colored by digit labels to assess separability.
Perform basic principal component analysis in MATLAB by generating random two‑D data, computing covariance and eigenvectors, projecting onto the first principal component, and visualizing the data and its projection.
Apply principal component analysis to the iris dataset in MATLAB using the statistics toolbox, transform data to two components, and visualize with a color-coded scatter plot by class.
Apply principal component analysis in MATLAB to a handwritten digits dataset, reducing 64-input images to two principal components, visualize separations with a scatter plot, and assess data preservation via eigenvalues.
Principal Component Analysis (PCA) is an unsupervised learning algorithms and it is mainly used for dimensionality reduction, lossy data compression and feature extraction. It is the mostly used unsupervised learning algorithm in the field of Machine Learning.
In this video tutorial, after reviewing the theoretical foundations of Principal Component Analysis (PCA), this method is implemented step-by-step in Python and MATLAB. Also, PCA is performed on Iris Dataset and images of hand-written numerical digits, using Scikit-Learn (Python library for Machine Learning) and Statistics Toolbox of MATLAB. Also the projects files are available to download at the end of this post.