From morg@n@em@||box @end|ng |rom gm@||@com  Fri Oct 11 19:52:22 2019
From: morg@n@em@||box @end|ng |rom gm@||@com (Morgan Morgan)
Date: Fri, 11 Oct 2019 18:52:22 +0100
Subject: [Rd] New matrix function
In-Reply-To: <CAL6gwn+cKv=MJzLdqExP749frcPC0w9SR5vP4+YjARa=FzxqZg@mail.gmail.com>
References: <CAL0QV_OHN1+c2ZMO28v9gB1Y-0c+2zL57bDCgcZse13bZ8--eQ@mail.gmail.com>
 <43cbad8a-af09-0a9d-c66d-2476aee555aa@gmail.com>
 <CAL0QV_PcL25UttJNJF9ED-xj5z1gBHHSHozG584=WDW6uzUXRw@mail.gmail.com>
 <CAOQ5NyesrhA_yALGN8=kmO-T8vM5HqDAjiLooJUVLpGceHhp0w@mail.gmail.com>
 <CAL0QV_Mi_4uL-Ssc8CqtOZGVTfu46KfVbDdZD3TF_cDd-dvXKA@mail.gmail.com>
 <CAL6gwn+cKv=MJzLdqExP749frcPC0w9SR5vP4+YjARa=FzxqZg@mail.gmail.com>
Message-ID: <CAL0QV_N=LiXjw6xD-=+o-PGicAOj02h=KE9TW0id7=280Y6CnQ@mail.gmail.com>

Your answer makes much more sense to me.
I will probably end up adding the function to a package.
Some processes and decisions on how R is developed seems to be obscure to
me.

Thank you
Morgan

On Fri, 11 Oct 2019 15:30 Avraham Adler, <avraham.adler at gmail.com> wrote:

> It?s rather difficult. For example, the base R Kendall tau is written with
> the naive O(n^2). The much faster O(n log n) implementation was programmed
> and is in the pcaPP package. When I say much faster, I mean that my
> implementation in Excel VBA was faster than R for 10,000 or so pairs.
> R-Core decided not to implement that code, and instead made a note about
> the faster implementation living in pcaPP in the help for ?cor?. See [1]
> for the 2012 discussion. My point is it?s really really difficult to get
> something in Base R. Develop it well, put it in a package, and you have
> basically the same result.
>
> Avi
>
> [1] https://stat.ethz.ch/pipermail/r-devel/2012-June/064351.html
>
> On Fri, Oct 11, 2019 at 9:55 AM Morgan Morgan <morgan.emailbox at gmail.com>
> wrote:
>
>> How do you prove usefulness of a feature?
>> Do you have an example of a feature that has been added after proving to
>> be
>> useful in the package space first?
>>
>> Thank you,
>> Morgan
>>
>> On Fri, 11 Oct 2019 13:53 Michael Lawrence, <lawrence.michael at gene.com>
>> wrote:
>>
>> > Thanks for this interesting suggestion, Morgan. While there is no strict
>> > criteria for base R inclusion, one criterion relevant in this case is
>> that
>> > the usefulness of a feature be proven in the package space first.
>> >
>> > Michael
>> >
>> >
>> > On Fri, Oct 11, 2019 at 5:19 AM Morgan Morgan <
>> morgan.emailbox at gmail.com>
>> > wrote:
>> >
>> >> On Fri, 11 Oct 2019 10:45 Duncan Murdoch, <murdoch.duncan at gmail.com>
>> >> wrote:
>> >>
>> >> > On 11/10/2019 6:44 a.m., Morgan Morgan wrote:
>> >> > > Hi All,
>> >> > >
>> >> > > I was looking for a function to find a small matrix inside a larger
>> >> > matrix
>> >> > > in R similar to the one described in the following link:
>> >> > >
>> >> > >
>> >> >
>> >>
>> https://www.mathworks.com/matlabcentral/answers/194708-index-a-small-matrix-in-a-larger-matrix
>> >> > >
>> >> > > I couldn't find anything.
>> >> > >
>> >> > > The above function can be seen as a "generalisation" of the "which"
>> >> > > function as well as the function described in the following post:
>> >> > >
>> >> > >
>> >> >
>> >>
>> https://coolbutuseless.github.io/2018/04/03/finding-a-length-n-needle-in-a-haystack/
>> >> > >
>> >> > > Would be possible to add such a function to base R?
>> >> > >
>> >> > > I am happy to work with someone from the R core team (if you wish)
>> and
>> >> > > suggest an implementation in C.
>> >> >
>> >> > That seems like it would sometimes be a useful function, and maybe
>> >> > someone will point out a package that already contains it.  But if
>> not,
>> >> > why would it belong in base R?
>> >> >
>> >>
>> >> If someone already implemented it, that would great indeed. I think it
>> is
>> >> a
>> >> very general and basic function, hence base R could be a good place for
>> >> it?
>> >>
>> >> But this is probably not a good reason; maybe someone from the R core
>> team
>> >> can shed some light on how they decide whether or not to include a
>> >> function
>> >> in base R?
>> >>
>> >>
>> >> > Duncan Murdoch
>> >> >
>> >>
>> >>         [[alternative HTML version deleted]]
>> >>
>> >> ______________________________________________
>> >> R-devel at r-project.org mailing list
>> >> https://stat.ethz.ch/mailman/listinfo/r-devel
>> >>
>> >
>> >
>> > --
>> > Michael Lawrence
>> > Scientist, Bioinformatics and Computational Biology
>> > Genentech, A Member of the Roche Group
>> > Office +1 (650) 225-7760
>> > michafla at gene.com
>> >
>> > Join Genentech on LinkedIn | Twitter | Facebook | Instagram | YouTube
>> >
>>
>>         [[alternative HTML version deleted]]
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel
>>
> --
> Sent from Gmail Mobile
>

	[[alternative HTML version deleted]]



[Rd] New matrix function
Morgan Morgan