Some preliminaries work on the unit systems. It's not over but Aaron advised to do a pull request to help the review (see https://groups.google.com/forum/?fromgroups#!topic/sympy/XbWxpKS6S94). The current main problem comes from the operations, since Mul does not know that it should combine units and quantities together first (see the last test for an example).
You can merge this Pull Request by running: git pull https://github.com/melsophos/sympy units Or you can view, comment on it, or merge it online at: https://github.com/sympy/sympy/pull/1389 -- Commit Summary -- * Implement dimensions for physical units. * First implementation of prefixes for physical units. * Basic implementation for unit systems, mainly their matrix form and * Begin to link units with systems and prepare the way to operations between units. * Explain philosophy of the unit implementation, improve change of * Rewriting of the Dimension class to make it hashable. * Use sympy Dict class for dimension. * Implement unit multiplication. * Implement unit power and division. * Implement nice-looking str and repr method and the management of factors. * Implement the Quantity class. * Fix some problems, e.g. operations resulting in dimensionless quantities. * Fix displaying for units. * Add links to idea in headers, try to improve multiplications. -- File Changes -- D sympy/physics/units.py (308) A sympy/physics/units/__init__.py (2) A sympy/physics/units/dimensions.py (177) A sympy/physics/units/mks.py (41) A sympy/physics/units/tests/test_dimensions.py (34) A sympy/physics/units/tests/test_units.py (111) A sympy/physics/units/units.py (581) M sympy/printing/str.py (7) M sympy/printing/tests/test_str.py (5) -- Patch Links -- https://github.com/sympy/sympy/pull/1389.patch https://github.com/sympy/sympy/pull/1389.diff --- Reply to this email directly or view it on GitHub: https://github.com/sympy/sympy/pull/1389 -- You received this message because you are subscribed to the Google Groups "sympy-patches" group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
