r - How do I replace exact set of words? -

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• making gsub replace entire words? 2 answers

i have set of words exclude analysis. example,

trash<- c("de" , "do", "das", ...., "da") # set can n elements  

also, have data.frame named matc 2 variables v1 , v2 apply replacements of each word in trash nothing.

when tried using following code:

for(k in 1:length(pr_us))  {    matc$v1<- gsub(pr_us[k],  "" , matc$v1 )    matc$v2<- gsub(pr_us[k],  "" , matc$v2 )  } 

the replacement isn't exact. in other words, if matc$v1 "maria da graça madalena", result "maria graça malena" , following result "maria graça madalena". tried this

for(k in 1:length(pr_us)) {   matc$v1<- gsub( paste0(pr_us[k], "\bb") , "" , matc$v1 )   matc$v2<- gsub( paste0(pr_us[k], "\bb") , "" , matc$v2 ) } 

but, not work.

is there solution avoiding loop? solution apply functions...

since matching word, more reasonable include space before , after trash word. specific example op gives, can be:

gsub("\\s+da\\s+", " ", "maria da graça madalena") [1] "maria graça madalena"