[R] About the multiprecision computing package in R

[Jeff Newmiller]

Not sure I understand the concern. IEEE 754 double precision floating point was invented to allow for avoiding loss of precision when manipulating single precision floating point numbers... but then C just ignores single precision and you are expected to know that the precision of your answers may only be relied on at single precision for certain operations.

Wouldn't you just set Rmpfr precision to double your actual desired precision and move on? Though I suppose you might consider  more than doubling the desired precision to deal with exponentiation [1].

[1] https://en.m.wikipedia.org/wiki/Extended_precision#Working_range

On March 14, 2020 1:10:19 PM PDT, J C Nash <profjcnash using gmail.com> wrote:
>Rmpfr does "support" matrix algebra, but I have been trying for some
>time to determine if it computes "double" precision (i.e., double the
>set level of precision) inner products. I suspect that it does NOT,
>which is unfortunate. However, I would be happy to be wrong about
>this.
>
>JN
>
>On 2020-03-14 3:41 p.m., Bert Gunter wrote:
>> Read its documentation yourself and unless you have good reason not
>to,
>> always cc the list (which I have done here).
>> 
>> 
>> Bert Gunter
>> 
>> "The trouble with having an open mind is that people keep coming
>along and
>> sticking things into it."
>> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>> 
>> 
>> On Sat, Mar 14, 2020 at 12:28 PM 林伟璐 <13917987541 using 163.com> wrote:
>> 
>>> Thanks. Does it support matrix algebra?
>>>
>>>
>>>
>>> 林伟璐
>>> 邮箱：13917987541 using 163.com
>>>
>>>
><https://maas.mail.163.com/dashi-web-extend/html/proSignature.html?iconUrl=http%3A%2F%2Fmail-online.nosdn.127.net%2F17c23bc1722125aa6261c33736f525c5.jpg&name=%E6%9E%97%E4%BC%9F%E7%92%90&uid=13917987541%40163.com&ftlId=1&items=%5B%22%E9%82%AE%E7%AE%B1%EF%BC%9A13917987541%40163.com%22%5D>
>>>
>>> 签名由 网易邮箱大师 <https://mail.163.com/dashi/dlpro.html?from=mail88> 定制
>>>
>>> On 03/15/2020 03:18, Bert Gunter <bgunter.4567 using gmail.com> wrote:
>>> Use google instead, as I recommended. If that's impossible in China,
>you
>>> should state that and what you tried (Baidu) in your query.
>>>
>>> You'll get the Rmpfr package.
>>>
>>> Bert Gunter
>>>
>>> "The trouble with having an open mind is that people keep coming
>along and
>>> sticking things into it."
>>> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>>>
>>>
>>> On Sat, Mar 14, 2020 at 11:48 AM 林伟璐 <13917987541 using 163.com> wrote:
>>>
>>>> Thanks, I tried Baidu but get nothing
>>>>
>>>>
>>>>
>>>> 林伟璐
>>>> 邮箱：13917987541 using 163.com
>>>>
>>>>
><https://maas.mail.163.com/dashi-web-extend/html/proSignature.html?iconUrl=http%3A%2F%2Fmail-online.nosdn.127.net%2F17c23bc1722125aa6261c33736f525c5.jpg&name=%E6%9E%97%E4%BC%9F%E7%92%90&uid=13917987541%40163.com&ftlId=1&items=%5B%22%E9%82%AE%E7%AE%B1%EF%BC%9A13917987541%40163.com%22%5D>
>>>>
>>>> 签名由 网易邮箱大师 <https://mail.163.com/dashi/dlpro.html?from=mail88> 定制
>>>>
>>>> On 03/15/2020 02:44, Bert Gunter <bgunter.4567 using gmail.com> wrote:
>>>> Here's a novel idea:
>>>> Do a google search on "multiprecision computing package R" for an
>answer.
>>>>
>>>> Bert Gunter
>>>>
>>>> "The trouble with having an open mind is that people keep coming
>along
>>>> and sticking things into it."
>>>> -- Opus (aka Berkeley Breathed in his "Bloom County" comic strip )
>>>>
>>>>
>>>> On Sat, Mar 14, 2020 at 10:36 AM 林伟璐 <13917987541 using 163.com> wrote:
>>>>
>>>>> Dear all
>>>>>
>>>>>
>>>>> I need a multiprecision computing package in R, if anyone in the
>list
>>>>> knows, please let me known...
>>>>>
>>>>>
>>>>> Many thanks
>>>>>
>>>>>
>>>>> Weilu Lin
>>>>>         [[alternative HTML version deleted]]
>>>>>
>>>>> ______________________________________________
>>>>> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>>>>> https://stat.ethz.ch/mailman/listinfo/r-help
>>>>> PLEASE do read the posting guide
>>>>> http://www.R-project.org/posting-guide.html
>>>>> and provide commented, minimal, self-contained, reproducible code.
>>>>>
>>>>
>> 
>> 	[[alternative HTML version deleted]]
>> 
>> ______________________________________________
>> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
>______________________________________________
>R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
>https://stat.ethz.ch/mailman/listinfo/r-help
>PLEASE do read the posting guide
>http://www.R-project.org/posting-guide.html
>and provide commented, minimal, self-contained, reproducible code.

-- 
Sent from my phone. Please excuse my brevity.