[R] find an empty char in the name of a vector

[arun]

Hi,

Hi,

If the names vector is similar to below:
v2 <- c("g_", "", " ","g2","        ", "g3")
grep("^$| +",v2)
#[1] 2 3 5
#or
 grep("^\\s*$",v2)
#[1] 2 3 5

A.K.


On Thursday, May 15, 2014 6:36 AM, arun <smartpink111 at yahoo.com> wrote:
Hi,
Assuming that this is the case:
v2 <- c("g_", "", "g2","g3")
 which(v2=="")
#[1] 2


##Second question
v1 <- c("g_", "g_w1", "g_w2", "g_bc3")
grepl("\\bg_\\b",v1)
#[1]  TRUE FALSE FALSE FALSE

v1[grepl("\\bg_\\b",v1)]
#[1] "g_"

A.K.




Hi,
I have a vector with the name of an element that is empty. How can I find out the index of this element? The following doesn't work:

empty.char = grep('[:blank:||:space:]' ,names(v))
if (length(empty.char)>0)
    ....

How about if the name of one element is g_ and the name of other elements g_anyword     where any word contain alphanumeric characters and I want to find the one whose name contain only g_?

Cheers,

Carol