Changes between Initial Version and Version 1 of Ticket #14972


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Timestamp:
07/25/13 20:30:02 (9 years ago)
Author:
gagern
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  • Ticket #14972 – Description

    initial v1  
    5959
    6060for some non-clashing variable name `t`.
     61
     62In comment:17:ticket:14403, burcin stated that a method to obtain new variable names should operate in constant time, everything else being to complicated. I agree that constant time would be desirable for all those cases where the variable name really doesn't matter, i.e. where the polynomial is only used internally, as a list of coefficients no mater the variable name. But wherever the polynomial might end in the hands of the user, I think a bit more work is warranted.
     63
     64I wonder whether it would be feasible to always explicitely state any variable name in the internal calls, thus avoiding the automatic selection, and leave the default argument case to users only. This would mean going over the whole codebase and replacing all calls of `.charpoly()` by `charpoly('x')`, all calls of `charpoly(*)` by `charpoly(*, 'x')`, and likewise for `characteristic_polynomial`. The non-method versions might be difficult to express in terms of regular expressions, but grepping for `charpoly` should highlight all use cases, and editor macros with a fall back to manual editing should see them adjusted.