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Algorithms

RRQR Factorization and Spanning Boxes

The famous QR factorization algorithm can be BLAS-3 optimized. Using the Woodbury matrix identity, we implement a block-based Rank-Revealing QR and point out a connection between pivot selection and object detection.

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Algorithms

Searching for a switch: the Circuit Breaker Panel problem

You want to identify the breaker switch for a particular outlet. This problem inspired me to write an article on Medium one day as I was thinking about the electric wiring at home. As you’ll see, there are commonalities between decidely challenging tasks in Machine Learning and the problems you

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Algorithms

Solve a Substitution Cipher with a Markov chain

There are k! substitution ciphers for an alphabet with k letters—too many for an exhaustive search. With a frequency-based approach adapted to the graph of alphabetic ciphers, we redefine the act of deciphering as a sampling problem suitable for a Metropolis-Hastings random walk. A substitution cipher is thus solvable with

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Algorithms

Plant Pairs on the Tufts Campus

In Spring of 2019 my Environmental Fieldwork class surveilled the herbaceous plants growing on and around the Tufts campus, recording their identities and locations into a GIS database. For a final project I created a simple Cartesian quadrature algorithm in Python to identify the distinct plant pairs most likely to

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