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  • Alex Wendland
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  • 2-SAT algorithm using SCC
  • 3-SAT is NP-complete
  • A finite tree that has more than one vertex must have at least two leaf vertices
  • A vertex with the highest post order number lies in a source SCC
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  • Check if a linear programme is solvable
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  • If a point in a linear programme has equal objective function to a point in its dual linear programme they are both optimal
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  • If two variables are independent joint entropy is additive
  • Image Segmentation
  • Image segmentation by max flow
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  • k-satisfiability problem (k-SAT problem)
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  • Knapsack Problem
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  • Zero-sum game

# Principle component analysis

Last edited: 2026-02-05

Principle component analysis is a linear dimension reduction algorithm. In concept principle component analysis find the axis along which the data has maximal variance if it were projected. It does this by finding the Eigenvector and Eigenvalues of the Covariance matrix . It uses these eigenvectors as a new basis of the data’s feature space.

It performs dimension reduction by only picking the eigenvectors which have the highest eigenvalue .

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