Karim Belabas on Tue, 22 Jan 2008 00:22:08 +0100


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Re: Why ellheight() only for minimal model?


* Jeroen Demeyer [2008-01-11 21:32]:
> I thought that I discovered a "bug" in ellheight(), but then I read the 
> documentation which states that E must be a standard minimal integral 
> model.  Would it not be possible instead to make ellheight() work for any 
> elliptic curve over Q? 

Sure, but this would be inefficient. Why waste 1ms recomputing a minimal
integral model in each height computation ? ( essentially,
factor( gcd(c4,c6) ) + elllocalred for each prime divisor found )

> In any case, I think the short help ?ellheight 
> should also specify this condition.

Agreed. Done in svn.

    K.B.
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Karim Belabas                  Tel: (+33) (0)5 40 00 26 17
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