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Attribute Grammars with Monads

Attribute grammars evaluate recursive data structures where inherited attributes are passed from the root to the leaves, and synthesised attributes are calculated in the leaves and passed back to the root. In “Beginning Haskell” pp343-4 (Apress ISBN 978-1-4302-6250-3), Alejandro Serrano Mena briefly discusses implementing attribute grammars using the Reader and Writer monads. He does notContinue reading “Attribute Grammars with Monads”

Observations of Kirch’s comet 1680-81

The observations Newton used to calculate the orbit of Kirch’s comet can be found in the tables in http://www.newtonproject.ox.ac.uk/view/texts/diplomatic/NATP00301 page 491. Observations up to 5 February are by Flamsteed; later observations are by Newton. Different versions of these tables exist. This version is sufficient to demonstrate the calculation. I have not found the Newton Project’sContinue reading “Observations of Kirch’s comet 1680-81”

Installing Diagrams

In preparation for my forthcoming series reproducing Newton’s calculation of the orbit of Kirch’s comet, I have been investigating Brent Yorgey’s Diagrams package. After successfully running the tutorial example in https://diagrams.github.io/doc/quickstart.html#your-first-diagram once, I had difficulties using it in new projects (and even reproducing the tutorial), for possibly related reasons: I usually use stack for development,Continue reading “Installing Diagrams”

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