[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread John Cremona
2008/4/23 David Harvey <[EMAIL PROTECTED]>: > > > On Apr 23, 2008, at 5:38 PM, Martin Albrecht wrote: > > > 3) search for a tri- or pentanomial with some code similar to the > > one in blog > > post > > You might want to check the NTL code for whether NTL "auto-detects" > that you have suppl

[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread John Cremona
Thanks for the debugging. I am trying it out (sage -br takes many minutes with this for some reason). If that works then I'll follow your suggestion to move this polynomial selection somewhere else. Should have a patch ready tomorrow... John 2008/4/23 Martin Albrecht <[EMAIL PROTECTED]>: > >

[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread David Harvey
On Apr 23, 2008, at 5:38 PM, Martin Albrecht wrote: > 3) search for a tri- or pentanomial with some code similar to the > one in blog > post You might want to check the NTL code for whether NTL "auto-detects" that you have supplied a sparse polynomial (and hence uses faster code for arith

[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread Martin Albrecht
On Wednesday 23 April 2008, John Cremona wrote: > Thanks, Martin. I agree with your comments. All I am really talking > about here is the time taken to construct the field -- I know that a > lot more work will be needed to get a really good finite field setup > in Sage (including arbitrary coerc

[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread John Cremona
Thanks, Martin. I agree with your comments. All I am really talking about here is the time taken to construct the field -- I know that a lot more work will be needed to get a really good finite field setup in Sage (including arbitrary coercions into extension fields, as previously discussed). I

[sage-devel] Re: construction of finite fields GF(2^n)

2008-04-23 Thread Martin Albrecht
On Wednesday 23 April 2008, John Cremona wrote: > There's a serious inefficiency in the construction of finite fields > GF(2^n) in Sage at the moment. > For n<=15 these are constructed of type > sage.rings.finite_field_givaro.FiniteField_givaro, about which I have > nothing to say now; for n>=16