Re: real polynomials

[Karim Belabas <Karim.Belabas@math.u-bordeaux.fr>]

* John Cremona [2015-11-06 17:51]:
> For some reason I thought that calling gdiv on two t_INTs would give a
> truncated answer. 

- gdiv() implements the '/' GP operator [ which doesn't truncate ]

- divii() returns the Euclidean quotient of two integers (hence truncates)

> In fact I wanted to make a t_INT out of the
> mantissa and then right-shift it by e places, but the function which
> does that does (I think?) truncate.

Shifting functions come in two variants: 

- gshift() [ truncates, implements the << and >> operators ]

- gmul2n() [ multiplies by 2^n; never truncates, so safe for use when n < 0 ]


Cheers,

    K.B.
--
Karim Belabas, IMB (UMR 5251)  Tel: (+33) (0)5 40 00 26 17
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