GNU Units

15 points by op


jdpage

If you have any interest in metrology, the definitions file (debian sources link) is very well-commented and includes a lot of interesting historical tidbits.

Some of the desk calculator features are very nice as well. For example, there are two multiplication operators (* and space) and two division operators (/ and |), the latter of each pair being higher precedence than either of the former, so 1 m / 5 s is in m/s, not meter-seconds.

I definitely recommend reading the manual if you plan to use affine conversions, such as temperature. Scale conversions (that is, a temperature in Fahrenheit to the same in Celsius) and degree conversions (my terminology, I don't remember what units calls it; some number of degrees Fahrenheit to a number of degrees Celsius representing the same temperature delta) are both supported, which is useful but I struggle to remember how to invoke the one I want.

Also! It supports various global versions of imperial measures, and will pick a default for what a pound fluid ounce (EDITED: see fanf's comment below) is based on your locale. However, the other local variants are available prefixed, so if you have a recipe from somewhere else in the world that you're localising (or better yet, metricising) then it's very useful for that.