[Boost-bugs] [Boost C++ Libraries] #4011: Strange bug may be associated with rounded_transc_opp policy

Subject: [Boost-bugs] [Boost C++ Libraries] #4011: Strange bug may be associated with rounded_transc_opp policy
From: Boost C++ Libraries (noreply_at_[hidden])
Date: 2010-03-15 19:54:20

#4011: Strange bug may be associated with rounded_transc_opp policy
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 Reporter:  Vitor Vieira Lopes <vitor.lopes@…>        |       Owner:  bgubenko
     Type:  Bugs                                      |      Status:  new     
Milestone:  To Be Determined                          |   Component:  interval
  Version:  Boost 1.38.0                              |    Severity:  Problem 
 Keywords:                                            |  
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 When I evaluate the following expression:
 a = Interval(1.0, 3.0)[[BR]]
 exp( a * log(0.001) )[[BR]]

 I receive the result [nan ~ nan] when I select the rounded_transc_opp
 policy. However, if I select the rounded_transc_exact all goes well and I
 receive the expected result: [1E-9 ~ 0.001]

 If I select the rounded_transc_opp policy and evaluate the
 expression:[[BR]]
 exp( a * log(0.0001) )
 all works well and I receive the expected result: [1E-12 ~ 0.0001]
 also works well for:[[BR]]
 exp( a * log(0.0011) )
 but not with:[[BR]]
 exp( a * log(0.00101) )

 I hope that someone can look at this problem, since this is really a very
 strange situation.

 Keep up with this excellent work and
 best regards...

 Vitor

-- 
Ticket URL: <https://svn.boost.org/trac/boost/ticket/4011>
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