Hi Fergus, thank you for your comments! So, do you consider working on a Quantity porting worthwhile? It seems that you got some good experience by working on it, so you can probably give some better advice about the structure of that package.
Moreover, I'm wondering how much work would it require to try to allow symbolic support for SAGE for Quantities or any other units package. Regarding the output of such expression you wrote, I agree that it should give a standard unit output for each physical quantity, so by presetting SI (or imperial, or anything else), it should give just meters (or feets, or anything else)... Regards Maurizio On 16 Mar, 00:55, "fergusno...@gmail.com" <fergusno...@gmail.com> wrote: > Hi, > > Thanks for emailing me Nicolas. > > I had a quick play with writing a units extension really just to learn > more about SAGE. I've only just started writing this so its still a > way off being ready for prime time but so far you can create > quantities with units, manipulate them like any other number and > convert to different units. There is also a sub-library of common > physical constants with units. > > I hadn't heard of the Quantity package until just now but it looks > much more mature than what I have been working on. I took a slightly > different approach in that in my code quantities are always kept in SI > base units so simplification is never necessary but that means that > sometimes it makes assumptions about what units the user would like > the results in e.g. > > (10 * meter)**3 / (5 * ft)**2 > > will give 40 m**3/ft**2 in Quantity as it is unclear whether the user > wants the result in meters or feet and the user must explicitly > simplify the result to the unit they wanted, whereas in my code will > always output in meters and the user can convert it to feet if needed. > This also means you can add dissimilar units of the same > dimensionality and the result will just end up in SI units. > > I will clean up my code and make a little demo so people can play with > it when I have a bit more free time on tuesday, if anyone is > interested. I'm still keen to keep developing my implementation but I > can see that porting Quantity to work with SAGE might be a quicker way > to get a mature units system up and running. > > Thanks, > Fergus --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
