Matching a vector with a vector of patterns in R

Question

Given a vector of urls i want to filter these URLs and puling out only URLs matching a set of patterns.

/pages/
/econo/*
/categ/sub 

I am currently using the data.table package. for Matching a vector with a single pattern i use

urls[! urls %like% "/pages" ]

for multiple patterns this does not work

urls[! urls %like% c("/pages/","/categ/sub")  ]

Answer 1

Use | to separate the patterns:

urls[! urls %like% paste(c("/pages/","/categ/sub"),collapse="|")  ]

Example:

DT <- data.table(a = paste0(letters,rev(letters)))
DT[a %like% paste(c("a","b","c"),collapse="|")]

Edit: This also works without the data.table package:

   vector <- paste0(letters,rev(letters))
   patterns <- c("a","b","c")
   matches <- unique(grep(paste(patterns,collapse="|"), 
                        vector, value=TRUE))