The only thing that was argued to be or not be on, which is:
> The only way 0.1 - 1/10 is computed as zero is if the user forces exact
> numbers be converted to nearby floating-point numbers. In this case the
> two
> values coincide.
Cheers!
On Thu, Nov 10, 2011 at 20:14, Stavros Macrakis <macrakis at alum.mit.edu> wrote:
> *What* "seems to be the default"?
> ? ? ? ? ? ?-s
> On Thu, Nov 10, 2011 at 13:15, cheater cheater <cheater00 at gmail.com> wrote:
>>
>> That seems to be the default then, doesn't it?
>>
>> Cheers
>>
>> On Thu, Nov 10, 2011 at 19:04, Richard Fateman
>> <fateman at eecs.berkeley.edu> wrote:
>> > On 11/10/2011 9:30 AM, cheater cheater wrote:
>> >>
>> >> Hi Rene,
>> >> they do:
>> >>
>> >> (%i1) sqrt(0.1)-sqrt(1/10);
>> >> (%o1) ? ? ? ? ? ? ? ? ? ?.3162277660168379 - 1/sqrt(10)
>> >> (%i2) ev(sqrt(0.1)-sqrt(1/10),numer);
>> >> (%o2) ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 0.0
>> >>
>> >> You just have to invoke numeric evaluation.
>> >>
>> >> Hope this helps
>> >
>> > Actually, 0.1 is not equal to 1/10.
>> >
>> > 0.1 ?is a floating point number which is converted to double-float
>> > binary,
>> > in which internal form it is
>> > exactly equal to 3602879701896397/2^55.
>> >
>> > This is NOT exactly equal to 1/10. They differ by 1/180143985094819840
>> > or
>> > 1/(5*2^55).
>> >
>> > The only way 0.1 - 1/10 is computed as zero is if the user forces exact
>> > numbers be converted to nearby floating-point numbers. ?In this case the
>> > two
>> > values coincide.
>> >
>> >
>> >
>> >
>> >
>> >
>> >> On Thu, Nov 10, 2011 at 17:51, rene kaelin<renekaelin at gmx.ch> ?wrote:
>> >>>
>> >>> Dear maxima users
>> >>> Why don't both expressions simplify to zero?
>> >>> (%i1) sqrt(0.1)-sqrt(1/10);
>> >>> (%o1) .3162277660168379-1/sqrt(10)
>> >>> (%i2) 0.1^0.5-(1/10)^0.5;
>> >>> (%o2) 0.0
>> >>> Manual:
>> >>> Function: SQRT (X)the square root of X. It is represented internally
>> >>> by
>> >>> X^(1/2). Also see ROOTSCONTRACT. RADEXPAND[TRUE] - if TRUE will cause
>> >>> nth
>> >>> roots of factors of a product which are powers of n to be pulled
>> >>> outside
>> >>> of
>> >>> the radical, e.g. SQRT(16*X^2) will become 4*X only if RADEXPAND is
>> >>> TRUE.
>> >>> Maxima version: 5.21.1Maxima build date: 16:28 5/16/2010Host type:
>> >>> i686-apple-darwin10.3.0Lisp implementation type: SBCLLisp
>> >>> implementation
>> >>> version: 1.0.38
>> >>>
>> >>>
>> >>> _______________________________________________
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>> >>>
>> >>>
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>> >
>> >
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>
>