Thank you, Roger.  Kip Murray

Roger Hui wrote:
> FYI:  In J7.01 the monad ^...@j. is supported by special code,
> so that:
> 
>    ^...@o. 0 j. 0.5 * i. 3 4
> 1 0j1 _1 0j_1
> 1 0j1 _1 0j_1
> 1 0j1 _1 0j_1
> 
>    ^...@o. 0 j. 2e9 + 0.5 * i. 3 4
> 1 0j1 _1 0j_1
> 1 0j1 _1 0j_1
> 1 0j1 _1 0j_1
> 
> 
> 
> ----- Original Message -----
> From: DIETER ENSSLEN <[email protected]>
> Date: Tuesday, January 19, 2010 13:51
> Subject: [Jchat] J and CAS, and problems in CAS
> To: chat forum <[email protected]>
> 
>> CAS  computer algebra systems
>>
>> e^(pi *i)+ 1   actually equals  a nice zero, yes it is nice
>> OK  OK  OK
>>
>> I do look forward to more of CAS in J.
>>
>> But there lurk problems in that world, too:
>> The world's most powerful and best graphing calculator, the TI 
>> Nspire cas evaluates the integral from -1 to 1 of 1/sqrt(1-x^2) 
>>  nicely as 'pi' in symbol form.
>>
>> then if you ask for the approximation of that 'pi' you get a 
>> number that is different from the regular 'pi' by two 
>> significant digits?!   ..5862   vs   ..5898 , the last figures 
>> to 14 places. A difference of  -3.6e-12.  J gives   ..5897 931.
>>
>> this must make sense to some or many of you. Good luck in the 
>> move towards 'cas'
>>
>> by the way, this my computer does not let me type TI-Nspire 
>> followed with the capital letters CAS without dropping the line 
>> again and again and again. This too must make sense to several 
>> of you.
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