Or to return a logical value, i.e., TRUE if the column contains the value, FALSE
if it does not:
any( x[,2] == 'A501' )
-Don
--
Don MacQueen
Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062
Lab cell 925-724-7509
?On 8/13/18, 12:09 AM, "R-help on behalf of Albrecht Kauffmann"
<r-help-bounces at r-project.org on behalf of alkauffm at fastmail.fm>
wrote:
Hello Deepa,
sum(x[,2] == "A501")
or
which(x[,2] == "A501")
.
Best,
Albrecht
--
Albrecht Kauffmann
alkauffm at fastmail.fm
Am Mo, 13. Aug 2018, um 07:10, schrieb Deepa Maheshvare:
> Hello Everyone,
>
> I have a 1000 x 20 matrix. The second column of the matrix has the
names
> of identifiers. How do I check when a certain identifier is present in
> the set of 1000 identifier names present in the second column. For
> instance, let the names of identifiers be A1,A2,...A1000. I want to
> check whether A501 is present .How can this be checked?
>
> Any help will be highly appreciated.
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at 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 at 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.
Hi Don, When there is a list of identifier names that I want to check, the only way is to loop over each entry stored in the list of identifier names or is there is there any other shortcut? Many thanks for the response? On Mon, Aug 13, 2018 at 8:18 PM, MacQueen, Don <macqueen1 at llnl.gov> wrote:> Or to return a logical value, i.e., TRUE if the column contains the value, > FALSE if it does not: > > any( x[,2] == 'A501' ) > > -Don > -- > Don MacQueen > Lawrence Livermore National Laboratory > 7000 East Ave., L-627 > Livermore, CA 94550 > 925-423-1062 > Lab cell 925-724-7509 > > > > ?On 8/13/18, 12:09 AM, "R-help on behalf of Albrecht Kauffmann" < > r-help-bounces at r-project.org on behalf of alkauffm at fastmail.fm> wrote: > > Hello Deepa, > > sum(x[,2] == "A501") > or > which(x[,2] == "A501") > . > Best, > Albrecht > > > -- > Albrecht Kauffmann > alkauffm at fastmail.fm > > Am Mo, 13. Aug 2018, um 07:10, schrieb Deepa Maheshvare: > > Hello Everyone, > > > > I have a 1000 x 20 matrix. The second column of the matrix has the > names > > of identifiers. How do I check when a certain identifier is present > in > > the set of 1000 identifier names present in the second column. For > > instance, let the names of identifiers be A1,A2,...A1000. I want to > > check whether A501 is present .How can this be checked? > > > > Any help will be highly appreciated. > > > > > > [[alternative HTML version deleted]] > > > > ______________________________________________ > > R-help at 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 at 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]]
Use the %in% operator:
help('%in%')
e.g.
R > c("d", "v", "4", "s") %in%
letters
[1] TRUE TRUE FALSE TRUE
B.
> On 2018-08-13, at 23:36, Deepa <deepamahm.iisc at gmail.com> wrote:
>
> Hi Don,
>
> When there is a list of identifier names that I want to check, the only way
> is to loop over each entry stored in the list of identifier names or is
> there is there any other shortcut?
>
> Many thanks for the response?
>
> On Mon, Aug 13, 2018 at 8:18 PM, MacQueen, Don <macqueen1 at
llnl.gov> wrote:
>
>> Or to return a logical value, i.e., TRUE if the column contains the
value,
>> FALSE if it does not:
>>
>> any( x[,2] == 'A501' )
>>
>> -Don
>> --
>> Don MacQueen
>> Lawrence Livermore National Laboratory
>> 7000 East Ave., L-627
>> Livermore, CA 94550
>> 925-423-1062
>> Lab cell 925-724-7509
>>
>>
>>
>> ?On 8/13/18, 12:09 AM, "R-help on behalf of Albrecht
Kauffmann" <
>> r-help-bounces at r-project.org on behalf of alkauffm at
fastmail.fm> wrote:
>>
>> Hello Deepa,
>>
>> sum(x[,2] == "A501")
>> or
>> which(x[,2] == "A501")
>> .
>> Best,
>> Albrecht
>>
>>
>> --
>> Albrecht Kauffmann
>> alkauffm at fastmail.fm
>>
>> Am Mo, 13. Aug 2018, um 07:10, schrieb Deepa Maheshvare:
>>> Hello Everyone,
>>>
>>> I have a 1000 x 20 matrix. The second column of the matrix has the
>> names
>>> of identifiers. How do I check when a certain identifier is present
>> in
>>> the set of 1000 identifier names present in the second column. For
>>> instance, let the names of identifiers be A1,A2,...A1000. I want to
>>> check whether A501 is present .How can this be checked?
>>>
>>> Any help will be highly appreciated.
>>>
>>>
>>> [[alternative HTML version deleted]]
>>>
>>> ______________________________________________
>>> R-help at 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 at 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 at 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.
These seem to be basic R questions. You should spend time with an R tutorial or two for this sort of thing. This list is here to help, but you also need to do homework on your own if you have not already done so. Cheers, Bert 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 Mon, Aug 13, 2018 at 8:36 PM, Deepa <deepamahm.iisc at gmail.com> wrote:> Hi Don, > > When there is a list of identifier names that I want to check, the only way > is to loop over each entry stored in the list of identifier names or is > there is there any other shortcut? > > Many thanks for the response? > > On Mon, Aug 13, 2018 at 8:18 PM, MacQueen, Don <macqueen1 at llnl.gov> wrote: > > > Or to return a logical value, i.e., TRUE if the column contains the > value, > > FALSE if it does not: > > > > any( x[,2] == 'A501' ) > > > > -Don > > -- > > Don MacQueen > > Lawrence Livermore National Laboratory > > 7000 East Ave., L-627 > > Livermore, CA 94550 > > 925-423-1062 > > Lab cell 925-724-7509 > > > > > > > > ?On 8/13/18, 12:09 AM, "R-help on behalf of Albrecht Kauffmann" < > > r-help-bounces at r-project.org on behalf of alkauffm at fastmail.fm> wrote: > > > > Hello Deepa, > > > > sum(x[,2] == "A501") > > or > > which(x[,2] == "A501") > > . > > Best, > > Albrecht > > > > > > -- > > Albrecht Kauffmann > > alkauffm at fastmail.fm > > > > Am Mo, 13. Aug 2018, um 07:10, schrieb Deepa Maheshvare: > > > Hello Everyone, > > > > > > I have a 1000 x 20 matrix. The second column of the matrix has the > > names > > > of identifiers. How do I check when a certain identifier is present > > in > > > the set of 1000 identifier names present in the second column. For > > > instance, let the names of identifiers be A1,A2,...A1000. I want to > > > check whether A501 is present .How can this be checked? > > > > > > Any help will be highly appreciated. > > > > > > > > > [[alternative HTML version deleted]] > > > > > > ______________________________________________ > > > R-help at 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 at 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 at 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]]
It depends on what you want to check. There are a lot of things you can check
without looping.
For example, if you want to check whether all of the first letters of the
identifier names are "A", you could do
table( substr(idnames,1,1))
to show you all of the first letters, and how many there are of each.
Like Bert said, some tutorials would be good. Even better would be to find
someone nearby who knows R really well. I think R is probably difficult to learn
all on one's own.
Small suggestion: be careful about using the word "list" in statements
like "a list of identifier names". It's ok in ordinary English,
but in R a "list" is a special kind of data structure. Better to say
"a vector of identifier names".
-Don
--
Don MacQueen
Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062
Lab cell 925-724-7509
From: Deepa <deepamahm.iisc at gmail.com>
Date: Monday, August 13, 2018 at 8:36 PM
To: "MacQueen, Don" <macqueen1 at llnl.gov>, array R-help
<r-help at r-project.org>
Subject: Re: [R] searching for a specific row name in R
Hi Don,
When there is a list of identifier names that I want to check, the only way is
to loop over each entry stored in the list of identifier names or is there is
there any other shortcut?
Many thanks for the response?
On Mon, Aug 13, 2018 at 8:18 PM, MacQueen, Don <macqueen1 at
llnl.gov<mailto:macqueen1 at llnl.gov>> wrote:
Or to return a logical value, i.e., TRUE if the column contains the value, FALSE
if it does not:
any( x[,2] == 'A501' )
-Don
--
Don MacQueen
Lawrence Livermore National Laboratory
7000 East Ave., L-627
Livermore, CA 94550
925-423-1062
Lab cell 925-724-7509
On 8/13/18, 12:09 AM, "R-help on behalf of Albrecht Kauffmann"
<r-help-bounces at r-project.org<mailto:r-help-bounces at
r-project.org> on behalf of alkauffm at fastmail.fm<mailto:alkauffm at
fastmail.fm>> wrote:
Hello Deepa,
sum(x[,2] == "A501")
or
which(x[,2] == "A501")
.
Best,
Albrecht
--
Albrecht Kauffmann
alkauffm at fastmail.fm<mailto:alkauffm at fastmail.fm>
Am Mo, 13. Aug 2018, um 07:10, schrieb Deepa Maheshvare:
> Hello Everyone,
>
> I have a 1000 x 20 matrix. The second column of the matrix has the
names
> of identifiers. How do I check when a certain identifier is present in
> the set of 1000 identifier names present in the second column. For
> instance, let the names of identifiers be A1,A2,...A1000. I want to
> check whether A501 is present .How can this be checked?
>
> Any help will be highly appreciated.
>
>
> [[alternative HTML version deleted]]
>
> ______________________________________________
> R-help at r-project.org<mailto:R-help at 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 at r-project.org<mailto:R-help at 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]]