If I copy and paste this into a temp file, and load it, I get the same
spelling error you got.
If I replace the load keyword in my session with a.i.30 }. 41 {. 1!:1<
I get:
50 43 114 13 10 226 128 139 226 128 139
So it looks like you have a couple invisible white space unicode
sequences which J currently does not recognize as valid white space.
Confirming this, in my J6.02 session, if I position the cursor to the
right of the 'w' in while and then move my cursor one character to the
left, and hit delete twice, the 'while.' keyword changes color, and
when I load the file I do not get the spelling error.
FYI,
--
Raul
On Tue, Oct 18, 2011 at 1:09 PM, David Vaughan
<[email protected]> wrote:
> Hmm, now I'm getting a spelling error which doesn't seem to make sense:
>
> cf =: 3 : 0
> r=.%:y
> a=.<.1r2+r
> while. ({:a)~:2*{.a do. a=.a,<.1r2+{:r ] r=.r,%({:r)-{:a end.
> ]a
> )
> |spelling error
> |
> | ^
> | cf=: 3 :0
>
> It's like it's saying the error is above the first line. Also this is no
> different to the version I had before aside from the correction in the while
> loop.
>
> On 18 Oct 2011, at 18:00, Raul Miller wrote:
>
>> The first element of a is always 1.
>>
>> The last element of a is always an integer and so can never be 0.5.
>>
>> So the loop can never terminate.
>>
>> --
>> Raul
>>
>> On Tue, Oct 18, 2011 at 12:52 PM, David Vaughan
>> <[email protected]> wrote:
>>> Why does this not work? I had to interrupt it because it just froze doing
>>> nothing.
>>>
>>> cf =: 3 : 0
>>> r=.%:y
>>> a=.<.1r2+r
>>> while. ({.a)~:2*{:a do. a=.a,<.1r2+{:r ] r=.r,1%({:r)-{:a end.
>>> ]a
>>> )
>>> cf 2
>>> |attention interrupt: cf
>>> | cf 2
>>>
>>>
>>> On 18 Oct 2011, at 17:23, Raul Miller wrote:
>>>
>>>> The best I can think of at the moment is using x: on the floating
>>>> point value for an initial value and then newton's method to gain the
>>>> extra precision you want.
>>>>
>>>> --
>>>> Raul
>>>>
>>>> On Tue, Oct 18, 2011 at 12:09 PM, David Vaughan
>>>> <[email protected]> wrote:
>>>>> I'm hoping to write a verb to compute the continued fraction expansion of
>>>>> a square root. I've done it in Java though there are accuracy issues with
>>>>> floating points and speed issues with using exact numbers (you end up
>>>>> multiplying massive numbers in some cases). Is J equipped to deal with
>>>>> these problems or should I be looking for an alternative method entirely?
>>>>>
>>>>> On 18 Oct 2011, at 16:50, Raul Miller wrote:
>>>>>
>>>>>> On Tue, Oct 18, 2011 at 11:30 AM, David Vaughan
>>>>>> <[email protected]> wrote:
>>>>>>> Can J represent surds exactly instead of reverting to floating point?
>>>>>>> It would be more convenient if I could do that rather than storing the
>>>>>>> squared version.
>>>>>>
>>>>>> Yes, but by generating a verb which would generate the floating point
>>>>>> value and not as a number.
>>>>>>
>>>>>> cubeRootOf5=: %:&5 bind 3
>>>>>>
>>>>>> Of course you can manipulate the resulting numbers but those results
>>>>>> are still floating point:
>>>>>>
>>>>>> (cubeRootOf5 ^ 3:) ''
>>>>>> 5
>>>>>> 5-(cubeRootOf5 ^ 3:) ''
>>>>>> 8.88178e_16
>>>>>>
>>>>>> That said, in some cases, J can clean up floating point discrepancies
>>>>>>
>>>>>> 5-x:(cubeRootOf5 ^ 3:) ''
>>>>>> 0
>>>>>>
>>>>>> but that's from direct manipulation of the values and does not care
>>>>>> about delayed evaluation:
>>>>>>
>>>>>> 5-x:((3 %:5) ^ 3:) ''
>>>>>> 0
>>>>>>
>>>>>> Anyways, J implements the data structures to support symbolic
>>>>>> manipulation but it does not have a particularly large library of
>>>>>> prebuilt symbolic manipulation routines.
>>>>>>
>>>>>> FYI,
>>>>>>
>>>>>> --
>>>>>> Raul
>>>>>> ----------------------------------------------------------------------
>>>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>>>
>>>>> ----------------------------------------------------------------------
>>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>>>
>>>> ----------------------------------------------------------------------
>>>> For information about J forums see http://www.jsoftware.com/forums.htm
>>>
>>> ----------------------------------------------------------------------
>>> For information about J forums see http://www.jsoftware.com/forums.htm
>> ----------------------------------------------------------------------
>> For information about J forums see http://www.jsoftware.com/forums.htm
>
> ----------------------------------------------------------------------
> For information about J forums see http://www.jsoftware.com/forums.htm
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