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Re: [Bug-apl] number precision in saved workspaces
From: |
Xiao-Yong Jin |
Subject: |
Re: [Bug-apl] number precision in saved workspaces |
Date: |
Mon, 13 Jun 2016 09:24:42 -0500 |
Yes, they work. Thanks.
> On Jun 11, 2016, at 9:29 AM, Juergen Sauermann <address@hidden> wrote:
>
> Hi Xiao-Yong,
>
> thanks, fixed in SVN 740. I haven't checked )DUMP and )OUT but I suppose
> they work now since the fault was in the tokenizer (which is also used by
> )LOAD and )IN).
>
> /// Jürgen
>
>
> On 06/10/2016 10:34 PM, Xiao-Yong Jin wrote:
>> Hi Jürgen,
>>
>> Thanks. I found more floating point reproduction issues.
>>
>> ⎕PP←17
>> x-y←x←○3 4
>> 0 0
>> x-⍎⍕x
>> 0 1.7763568394002505E¯15
>> x-¯14⎕CR 14⎕CR x
>> 0 0
>> 2⎕TF 2⎕TF ‘y'
>> y
>> y
>> 9.4247779607693793 12.566370614359172
>> x
>> 9.4247779607693793 12.566370614359172
>> x-○3 4
>> 0 0
>> y-○3 4
>> 0 ¯1.7763568394002505E¯15
>> x-y
>> 0 1.7763568394002505E¯15
>> 9.4247779607693793 12.566370614359172-○3 4
>> 0 ¯1.7763568394002505E¯15
>>
>>
>> The exact representation by 14⎕CR works great (as in one of the ISO CF
>> implementations), but both ⎕TF and ⍎⍕ fail to reproduce the exact number.
>>
>> Since you last change, the )save )load does keep the exact values, and I
>> looked at the saved workspace file, the numbers are
>> 146 <Ravel vid="1" cells="⁴9.4247779607693793⁴12.566370614359171"/>
>> 147 <Ravel vid="2" cells="⁴9.4247779607693793⁴12.566370614359172"/>
>> 185 <Symbol name="x" stack-size="1">
>> 186 <Variable vid="2"/>
>> 187 </Symbol>
>> 188
>> 189 <Symbol name="y" stack-size="1">
>> 190 <Variable vid="1"/>
>> 191 </Symbol>
>> Here, the last digit of y is 1 instead of 2, as shown in the REPL.
>>
>> So it seems the routine used to format numbers has some problem with the
>> last digits, even if with ⎕PP=17? Or it’s just the reader has some problem?
>>
>> In addition, )dump and )out still changes the floating point number, but
>> perhaps that is the same issue as in ⎕TF and ⍎⍕?
>>
>>
>>> On Jun 7, 2016, at 3:29 PM, Juergen Sauermann <address@hidden>
>>> wrote:
>>>
>>> Hi Xiao-Yong,
>>>
>>> OK - SVN 739.
>>>
>>> /// Jürgen
>>>
>>>
>>> On 06/07/2016 08:16 PM, Xiao-Yong Jin wrote:
>>>
>>>> Hi Jürgen,
>>>>
>>>> Thanks, though the current behavior still does not give the exact number
>>>> bit by bit. Can you change it to %.17g, or
>>>> std::numeric_limits<double>::max_digits10?
>>>>
>>>> In addition, is it OK to raise the maximum allowed ⎕PP to 17?
>>>>
>>>> Best,
>>>> Xiao-Yong
>>>>
>>>>
>>>>
>>>>> On Jun 7, 2016, at 12:37 PM, Juergen Sauermann <address@hidden>
>>>>>
>>>>> wrote:
>>>>>
>>>>> Hi Xiao-Yong,
>>>>>
>>>>> thanks, fixed in SVN 738.
>>>>>
>>>>> /// Jürgen
>>>>>
>>>>>
>>>>> On 06/07/2016 08:13 AM, Xiao-Yong Jin wrote:
>>>>>
>>>>>
>>>>>> Hello,
>>>>>>
>>>>>> Is the following behavior intended? Note the x value after load.
>>>>>>
>>>>>> )clear
>>>>>> CLEAR WS
>>>>>> x←.12345678901234567890
>>>>>> ⎕pp←16
>>>>>> x
>>>>>> 0.1234567890123457
>>>>>> )wsid tmp
>>>>>> WAS CLEAR WS
>>>>>> )save tmp
>>>>>> 2016-06-07 01:09:15 (GMT-5)
>>>>>> )clear
>>>>>> CLEAR WS
>>>>>> )load tmp
>>>>>> SAVED 2016-06-07 01:09:15 (GMT-5)
>>>>>> x
>>>>>> 0.123457
>>>>>> ⎕pp
>>>>>> 16
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>>>>>
>>
>
- [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/07
- Re: [Bug-apl] number precision in saved workspaces, Juergen Sauermann, 2016/06/07
- Re: [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/07
- Re: [Bug-apl] number precision in saved workspaces, Juergen Sauermann, 2016/06/07
- Re: [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/10
- Re: [Bug-apl] number precision in saved workspaces, Juergen Sauermann, 2016/06/11
- Re: [Bug-apl] number precision in saved workspaces,
Xiao-Yong Jin <=
- Re: [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/15
- Re: [Bug-apl] number precision in saved workspaces, Christian Robert, 2016/06/15
- Re: [Bug-apl] number precision in saved workspaces, Juergen Sauermann, 2016/06/16
- Re: [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/16
- Re: [Bug-apl] number precision in saved workspaces, Juergen Sauermann, 2016/06/16
- Re: [Bug-apl] number precision in saved workspaces, Xiao-Yong Jin, 2016/06/16