thr3ads.net - R help - [R] Extract student ID that match certain criteria [Mar 2017]

If this information is useful, please help other people find it:
Share via:

roslinazairimah zakaria

2017-Mar-13 03:32 UTC

[R] Extract student ID that match certain criteria

Dear r-users,

I have this list of student ID,

dt <- c(AA14068, AA13194, AE11054, AA12251, AA13228, AA13286, AA14090,
AA13256, AA13260, AA13291, AA14099, AA15071, AA13143, AA14012, AA14039,
AA15018, AA13234, AA13149, AA13282, AA13218)

and I would like to extract all student of ID AA14... only.

I search and tried substrt, subset and select but it fail.

 substr(FKASA$STUDENT_ID, 2, nchar(string1))
Error in nchar(string1) : 'nchar()' requires a character
vector> subset(FKASA, STUDENT_ID=="AA14" ) [1] FAC_CODE    FACULTY     STUDENT_ID  NAME        PROGRAM     KURSUS
 CGPA        ACT_SS      ACT_VAL     ACT_CS      ACT_LED     ACT_PS
 ACT_IM
[14] ACT_ENT     ACT_CRE     ACT_UNI     ACT_VOL...

Thank you so much for your help.

How do I do it?
-- 
*Roslinazairimah Zakaria*
*Tel: +609-5492370; Fax. No.+609-5492766*

*Email: roslinazairimah at ump.edu.my <roslinazairimah at ump.edu.my>;
roslinaump at gmail.com <roslinaump at gmail.com>*
Faculty of Industrial Sciences & Technology
University Malaysia Pahang
Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia

	[[alternative HTML version deleted]]

Bert Gunter

2017-Mar-13 03:51 UTC

head link

[R] Extract student ID that match certain criteria

1. Your code is incorrect. All entries are character strings and must be quoted.

2. See ?grep  and note in particular (in the "Value" section):

"grep(value = TRUE) returns a character vector containing the selected
elements of x (after coercion, preserving names but no other
attributes)."


3. While the fixed = TRUE option will work here, you may wish to learn
about "regular expressions", which can come in very handy for
character string manipulation tasks. ?regex in R has a terse, but I
have found comprehensible, discussion. There are many good gentler
tutorials on the web, also.


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 Sun, Mar 12, 2017 at 8:32 PM, roslinazairimah zakaria
<roslinaump at gmail.com> wrote:> Dear r-users,
>
> I have this list of student ID,
>
> dt <- c(AA14068, AA13194, AE11054, AA12251, AA13228, AA13286, AA14090,
> AA13256, AA13260, AA13291, AA14099, AA15071, AA13143, AA14012, AA14039,
> AA15018, AA13234, AA13149, AA13282, AA13218)
>
> and I would like to extract all student of ID AA14... only.
>
> I search and tried substrt, subset and select but it fail.
>
>  substr(FKASA$STUDENT_ID, 2, nchar(string1))
> Error in nchar(string1) : 'nchar()' requires a character vector
>> subset(FKASA, STUDENT_ID=="AA14" )
>  [1] FAC_CODE    FACULTY     STUDENT_ID  NAME        PROGRAM     KURSUS
>  CGPA        ACT_SS      ACT_VAL     ACT_CS      ACT_LED     ACT_PS
>  ACT_IM
> [14] ACT_ENT     ACT_CRE     ACT_UNI     ACT_VOL...
>
> Thank you so much for your help.
>
> How do I do it?
> --
> *Roslinazairimah Zakaria*
> *Tel: +609-5492370; Fax. No.+609-5492766*
>
> *Email: roslinazairimah at ump.edu.my <roslinazairimah at
ump.edu.my>;
> roslinaump at gmail.com <roslinaump at gmail.com>*
> Faculty of Industrial Sciences & Technology
> University Malaysia Pahang
> Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia
>
>         [[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.

roslinazairimah zakaria

2017-Mar-13 04:37 UTC

head link

[R] Extract student ID that match certain criteria

Hi Bert,

Thank you so much for your help.  However I don't really sure what is the
use of y values.  Can we do without it?

x <- as.character(FKASA$STUDENT_ID)
y <- c(1,786)
My.Data <- data.frame (x,y)

My.Data[grep("^AA14", My.Data$x), ]

I got the following data:

          x   y
1   AA14068   1
7   AA14090   1
11  AA14099   1
14  AA14012 786
15  AA14039   1
22  AA14251 786

On Mon, Mar 13, 2017 at 11:51 AM, Bert Gunter <bgunter.4567 at gmail.com>
wrote:
> 1. Your code is incorrect. All entries are character strings and must be
> quoted.
>
> 2. See ?grep  and note in particular (in the "Value" section):
>
> "grep(value = TRUE) returns a character vector containing the selected
> elements of x (after coercion, preserving names but no other
> attributes)."
>
>
> 3. While the fixed = TRUE option will work here, you may wish to learn
> about "regular expressions", which can come in very handy for
> character string manipulation tasks. ?regex in R has a terse, but I
> have found comprehensible, discussion. There are many good gentler
> tutorials on the web, also.
>
>
> 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 Sun, Mar 12, 2017 at 8:32 PM, roslinazairimah zakaria
> <roslinaump at gmail.com> wrote:
> > Dear r-users,
> >
> > I have this list of student ID,
> >
> > dt <- c(AA14068, AA13194, AE11054, AA12251, AA13228, AA13286,
AA14090,
> > AA13256, AA13260, AA13291, AA14099, AA15071, AA13143, AA14012,
AA14039,
> > AA15018, AA13234, AA13149, AA13282, AA13218)
> >
> > and I would like to extract all student of ID AA14... only.
> >
> > I search and tried substrt, subset and select but it fail.
> >
> >  substr(FKASA$STUDENT_ID, 2, nchar(string1))
> > Error in nchar(string1) : 'nchar()' requires a character
vector
> >> subset(FKASA, STUDENT_ID=="AA14" )
> >  [1] FAC_CODE    FACULTY     STUDENT_ID  NAME        PROGRAM    
KURSUS
> >  CGPA        ACT_SS      ACT_VAL     ACT_CS      ACT_LED     ACT_PS
> >  ACT_IM
> > [14] ACT_ENT     ACT_CRE     ACT_UNI     ACT_VOL...
> >
> > Thank you so much for your help.
> >
> > How do I do it?
> > --
> > *Roslinazairimah Zakaria*
> > *Tel: +609-5492370; Fax. No.+609-5492766*
> >
> > *Email: roslinazairimah at ump.edu.my <roslinazairimah at
ump.edu.my>;
> > roslinaump at gmail.com <roslinaump at gmail.com>*
> > Faculty of Industrial Sciences & Technology
> > University Malaysia Pahang
> > Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia
> >
> >         [[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.
>


-- 
*Roslinazairimah Zakaria*
*Tel: +609-5492370; Fax. No.+609-5492766*

*Email: roslinazairimah at ump.edu.my <roslinazairimah at ump.edu.my>;
roslinaump at gmail.com <roslinaump at gmail.com>*
Faculty of Industrial Sciences & Technology
University Malaysia Pahang
Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia

	[[alternative HTML version deleted]]

Jim Lemon

2017-Mar-13 10:20 UTC

head link

[R] Extract student ID that match certain criteria

Hi Roslinazairimah,
What you seem to want is fairly simple:

dt<-c("AA14068","AA13194","AE11054","AA12251","AA13228",
 
"AA13286","AA14090","AA13256","AA13260","AA13291",
 
"AA14099","AA15071","AA13143","AA14012","AA14039",
 
"AA15018","AA13234","AA13149","AA13282","AA13218")
dt[grep(pattern="AA14",dt)]
[1] "AA14068" "AA14090" "AA14099"
"AA14012" "AA14039"

However, as others have suggested, you may want a more general
solution that involves a variable pattern.

Jim

On Mon, Mar 13, 2017 at 2:32 PM, roslinazairimah zakaria
<roslinaump at gmail.com> wrote:> Dear r-users,
>
> I have this list of student ID,
>
> dt <- c(AA14068, AA13194, AE11054, AA12251, AA13228, AA13286, AA14090,
> AA13256, AA13260, AA13291, AA14099, AA15071, AA13143, AA14012, AA14039,
> AA15018, AA13234, AA13149, AA13282, AA13218)
>
> and I would like to extract all student of ID AA14... only.
>
> I search and tried substrt, subset and select but it fail.
>
>  substr(FKASA$STUDENT_ID, 2, nchar(string1))
> Error in nchar(string1) : 'nchar()' requires a character vector
>> subset(FKASA, STUDENT_ID=="AA14" )
>  [1] FAC_CODE    FACULTY     STUDENT_ID  NAME        PROGRAM     KURSUS
>  CGPA        ACT_SS      ACT_VAL     ACT_CS      ACT_LED     ACT_PS
>  ACT_IM
> [14] ACT_ENT     ACT_CRE     ACT_UNI     ACT_VOL...
>
> Thank you so much for your help.
>
> How do I do it?
> --
> *Roslinazairimah Zakaria*
> *Tel: +609-5492370; Fax. No.+609-5492766*
>
> *Email: roslinazairimah at ump.edu.my <roslinazairimah at
ump.edu.my>;
> roslinaump at gmail.com <roslinaump at gmail.com>*
> Faculty of Industrial Sciences & Technology
> University Malaysia Pahang
> Lebuhraya Tun Razak, 26300 Gambang, Pahang, Malaysia
>
>         [[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 - Mar 2017 - Extract student ID that match certain criteria

[R] Extract student ID that match certain criteria

[R] Extract student ID that match certain criteria

[R] Extract student ID that match certain criteria

[R] Extract student ID that match certain criteria