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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”

Countdown 2

In my previous post, I bodged a function to aggregate additions and multiplications into a program based on individual binary operations. This is what it looks like if it is designed to use Sum’ (the prime disambiguates it from the built-in monoid) and Prod from the beginning. It is only a little shorter, and muchContinue reading “Countdown 2”

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