[R] Extract student ID that match certain criteria

[Jim Lemon]

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
>
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