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mrc-ide / covid-sim

This is the COVID-19 CovidSim microsimulation model developed by the MRC Centre for Global Infectious Disease Analysis hosted at Imperial College, London.
GNU General Public License v3.0
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You can't multiply two vectors to get another vector #424

Closed zebmason closed 4 years ago

zebmason commented 4 years ago

https://github.com/mrc-ide/covid-sim/blob/f6d40d605feeaac0d18ae256875808df42eecf92/src/Geometry/Vector2.cpp#L5

This has no basis in vector algebra so is dangerous

insidedctm commented 4 years ago

The operation results in both components of the Vector2 being squared. I'd guess this is a precursor to doing something like a distance calculation. How is it used in the main code? This should either be renamed or maybe a change to the interface to make it more obvious what the Vector2 operation is actually being used to do.

zebmason commented 4 years ago

The Vector2 class is used to represent both a vector and a diagonal matrix hence the mixed algebra