[R] Prime Factorization

[David Winsemius]

A further citation that answers the question I raised (and  
inaccurately predicted no value) regarding prime.sieve :

http://finzi.psych.upenn.edu/R/Rhelp02/archive/49773.html

This was found with Barons search facility set for rhelp postings:
http://search.r-project.org/cgi-bin/namazu.cgi?query=factorize+prime&max=100&result=normal&sort=score&idxname=functions&idxname=Rhelp08&idxname=Rhelp10&idxname=Rhelp02



On Sep 21, 2010, at 4:22 PM, David Winsemius wrote:

>
> On Sep 21, 2010, at 3:44 PM, Spencer Graves wrote:
>
>> Hello:
>>
>>     It's hard to RTFM if you don't know which FMTR.  I only found  
>> one with the "obvious search strategy" with my favorite search  
>> tools, which may nevertheless be unfamiliar to Cliff Clive.
>>
>> RSiteSearch('prime factorization') # produced 3 matches, the first  
>> of which is the "primeFactors" function in the "surveillance"  
>> package.
>>
>> install.packages('sos') # if you don't already have it
>> library(sos)
>> pf <- findFn('prime factorization') # only 3 matches
>> pf # open the result in a web browser with a link to the  
>> "primeFactors" function above.
>>
>>
>> DAVID:  You say there are "At least two." How can I find the other  
>> one?
>
> With my second favorite search strategy (using sos's "???" function)  
> and "prime factors" I got schoolmath's prime.factor() and  
> conf.design's factorize()
>
> (I had already gotten the same results at Baron's search page so I  
> conclude that it was pretty easy.)
>
> Going to a slightly more general search, "prime factor", I also  
> found another factorize() in the elliptic package.
>
> With ???"prime factor*" I got 147 hits but have not had the time to  
> thoroughly search through them to see if I can get any more.
>
> (I do see another function,  primesieve, in spuRs but it doesn't  
> appear to factorize.)
>
> Stopping at one search strategy seems to severely limit the values  
> of a search engine.
>
> -- 
> David.
>
>
>>
>>
>>     Thanks,
>>     Spencer
>>
>>
>> On 9/21/2010 11:14 AM, David Winsemius wrote:
>>>
>>> On Sep 21, 2010, at 11:33 AM, Cliff Clive wrote:
>>>
>>>>
>>>> Hi everyone, I have a very quick question:
>>>>
>>>> Is there a ready-made function in R or any R packages to find the  
>>>> prime
>>>> factorization of an integer?
>>>
>>> Yes. At least two. The obvious search strategy with your favrite  
>>> search tool should work well.
>>>
>>
>>
>> -- 
>> Spencer Graves, PE, PhD
>> President and Chief Operating Officer
>> Structure Inspection and Monitoring, Inc.
>> 751 Emerson Ct.
>> San José, CA 95126
>> ph:  408-655-4567
>>
>
> David Winsemius, MD
> West Hartford, CT
>
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David Winsemius, MD
West Hartford, CT