Re: [sage-devel] help with QQbar conversion to complex number

2014-11-24 Thread Ben Hutz
hmm...one more question here then I'll stop, as this is turning into more like a sage-support discussion as opposed to sage-devel. This does seem to be doing a good job with high enough precision specified. What is the best way to compare two such interval numbers? The multipliers (after applyi

Re: [sage-devel] help with QQbar conversion to complex number

2014-11-24 Thread Jonas Jermann
Hi In particular: Try .simplify()! In my case that produced an improvement factor >1000 in some cases. Best Jonas On 24.11.2014 20:54, Ben Hutz wrote: Thanks Vincent. I can give that a try. We did try to approximate earlier with CC and the errors were compounding too much (we do a bunch m

Re: [sage-devel] help with QQbar conversion to complex number

2014-11-24 Thread Ben Hutz
Thanks Vincent. I can give that a try. We did try to approximate earlier with CC and the errors were compounding too much (we do a bunch more stuff after this), but maybe approximating the roots with CIF will do a better job. It sounds like the recursion depth error is actually expected for num

Re: [sage-devel] help with QQbar conversion to complex number

2014-11-24 Thread Vincent Delecroix
Hi Ben, You are dealing with complicated numbers, it is not surprising that things like "exactify" or "__cmp__" lead to maximum recursion errors. If you want something faster than QQbar you can either: - do approximation earlier in the code - try to work with number fields Note that your exampl

[sage-devel] help with QQbar conversion to complex number

2014-11-24 Thread Ben Hutz
I'm having trouble with getting a complex approximation to a QQbar number. We're working with symmetric polynomials of multipliers of periodic points, so the numbers generated are complicated and the failure occurs fairly far along in the computation, so the code to generate the error is a littl