[R] Print occurrence / positions of words

[arun]

Hi,
May be this helps:
vec<- "this is a nice text with nice characters" 
library(stringr)
 vec2<-unlist(str_match_all(vec,"\\w+"))

#or
# vec2<-str_split(vec," ")[[1]]

res<-unique(lapply(vec2,function(x) which(!is.na(match(vec2,x)))))
 names(res)<- unique(vec2)
res
#$this
#[1] 1
#
#$is
#[1] 2
#
#$a
#[1] 3
#
#$nice
#[1] 4 7
#
#$text
#[1] 5
#
#$with
#[1] 6
#
#$characters
#[1] 8
A.K.

>Hi, 
>I have tried some different packages in order to build a R program 
which will take as input a text file, produce a list of the words inside
 that file. Each >word should have a vector with all the places that this
 word exist in the file. 
>As an example, if the text file has the string: 
>
>"this is a nice text with nice characters" 
>
>The output should be something like: 
>$this   
>[1] 1 
>$is       
>[1] 2 
>$a         
>[1] 3 
>$nice     
>[1] 4 7 
>$text   
>[1] 5 
>$with   
>[1] 6 
>$characters 
>[1] 8 

>A useful post which i came across here was http://r.789695.n4.nabble.com/Memory-usage-in-R-grows-considerably-while-calculating-word-frequencies-td4644053.html . However it doesnt include the positions of each words. 
>A similar function which i found through the documentation i guess 
it's the "str_locate", however i want to count "words" and not 
"characters". 

>Any guidance of what packages / techniques to use on that, would be really appreciated 
>Thank you.