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Re: Bug 1+4/10

  • To: mathgroup at smc.vnet.net
  • Subject: [mg120063] Re: Bug 1+4/10
  • From: "slawek" <slawek at host.pl>
  • Date: Thu, 7 Jul 2011 07:32:00 -0400 (EDT)
  • References: <201107060940.FAA29406@smc.vnet.net> <iv1fj0$vp$1@smc.vnet.net>

U¿ytkownik "Patrick Scheibe" <pscheibe at trm.uni-leipzig.de> napisa³ w 
wiadomo¶ci grup dyskusyjnych:iv1fj0$vp$1 at smc.vnet.net...
> please, before make a posting like that make sure you have understood
> the basics of how numbers are stored in a computer.

You should notice, that Mathematica is not Visual Basic, but a computer 
algebra program.

> You could have used the subject "unexpected behavior" and the body
> should have contained something like "I don't understand.." or "can 
> someone
> explain...", but this is purely offensive so I won't comment it.

If Mathematica answer that a == b is true, then Mathematica should also 
answer that N[a] == N[b] is true. It is trivial.

You can, poor boy, check that  1.4 == 1+1/4 gives True, but N[1.4, 30] gives 
different result than N[1+1/4, 30] .

It is not good for "the most advanced computer algebra program".

Nevertheless, it is not very bad for your Visual Basic programs, which 
operates on 56 bits of the mantissa.

q.e.d. 



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