Talk:Unicode polynomial equation: Difference between revisions
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Cheers for that. Thank Zeus that we are all different. <!-- removed comment as it was too ambiguous, my apologies to all. --> [[User:NevilleDNZ|NevilleDNZ]] 09:33, 19 November 2011 (UTC)
The problem with removing commas is that the input string might have some numbers inside it whether the comma is used as a decimal point (common in continental european number formatting, whereas the UK and US use a period for that). This is very nasty, and wikipedia [[wp:Decimal mark|goes to some length]] on the subject's background. I recommend dropping that part of the task (though removing spaces between digit sequences ''is'' fine; it's not ambiguous except in situations which aren't polynomials at all). –[[User:Dkf|Donal Fellows]] 21:16, 14 January 2012 (UTC)
: That is not strictly true, though it could well be true for the definition of this task: J will represent polynomials as a space separated list of numeric coefficients (with constant being the first number). --[[User:Rdm|Rdm]] 23:44, 14 January 2012 (UTC)
:: That sounds more like an internal representation (and is actually similar to the rep I'd use in Tcl). –[[User:Dkf|Donal Fellows]] 13:46, 2 March 2012 (UTC)
::: It might be an internal format for TCL -- in TCL, I think everything is a string. In J, though, it the simplest parseable representation of a polynomial and could also be used as a serialized format. --[[User:Rdm|Rdm]] 14:19, 2 March 2012 (UTC)
:::: While it's somewhat inaccurate to say everything is a string (“all values are ''serializable''” would be closer to the truth as implemented, though Tcl practitioners tend to say “everything is a string” as a way to teach noobs) when it comes to rendering formats then while it is possible to do it that way, it isn't something that you'd want to expose to a non-programmer friend. Serializing as a “human-readable” format makes a bunch more sense given the general thrust of this task. (I suppose it would also be reasonable to use XML or JSON but that would increase the “ewwww!” factor…) Unfortunately, there's no way to reconcile the space-separated list format with the way that other languages treat spaces in digit sequences as ignorable; there really are totally incompatible interpretations of the same byte sequence. (The disadvantage of an undecorated number list is that there's no way to know if it is “big-endian” or “little-endian”, i.e., if the first element represents the most significant or least significant term. It might be “obvious” which it is, but I bet some people will get it wrong anyway.) –[[User:Dkf|Donal Fellows]] 15:53, 2 March 2012 (UTC)
::::: Certainly. This was originally an illustration of an issue with this task, which is that instead of a precise specification it makes ambiguous use of existential operators. I just got sidetracked. --[[User:Rdm|Rdm]] 16:29, 2 March 2012 (UTC)
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