#19822: Fast polynomial evaluation fmpz_poly/ZZX with mpfr/mpfi input
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       Reporter:  vdelecroix         |        Owner:
           Type:  enhancement        |       Status:  needs_work
       Priority:  major              |    Milestone:  sage-7.0
      Component:  algebra            |   Resolution:
       Keywords:                     |    Merged in:
        Authors:  Vincent Delecroix  |    Reviewers:  Jeroen Demeyer
Report Upstream:  N/A                |  Work issues:
         Branch:                     |       Commit:
  u/vdelecroix/19822                 |  5562a78b592125e698021743d545f176cc0604bb
   Dependencies:                     |     Stopgaps:
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Comment (by vdelecroix):

 I attached files which compare the various possibilities for Horner
 scheme:

  - `eval1`: the current version which is straightforward Horner expansion
 (red)
  - `eval2`: the same but skip addition if the term is 0 (green)
  - `eval3`: use `mpfr_pow` (blue)

 There are files `degree_{deg}_{prec}.png` for fixed degrees where the
 number of terms vary and `poly_{deg}_{nb_terms}.png` where the percision
 vary.

 [[Image(degree_20_64.png,45%)]] [[Image(degree_20_256.png,45%)]]

 [[Image(poly_20_2.png,45%)]] [[Image(poly_20_13.png,45%)]]

 `eval2` seems superior over `eval1`. But `eval3` seems only interesting
 for very sparse polynomials or very large precision. Indeed, for half
 dense polynomials (degree=20, nb_terms=13), `eval3` gets better than the
 other two around prec=2^8^

--
Ticket URL: <http://trac.sagemath.org/ticket/19822#comment:36>
Sage <http://www.sagemath.org>
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