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r - Filter a column which contains several keywords

I am trying to filter a column which contains several keywords (in this example dog and cat) but I am having problems as only the first element is being used.

id <- c(1:7)
type <- c("dog1","dog2" ,"cat1","cat2","zebra1", "parrot5", "elephant15")
filter1 <- c("dog","cat")
df1 <- data.frame(id,type)
dfilter <- df1[grep(filter1,df1$type),]
dfilter

I would be grateful for your help.

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grep can use | as an or, so why not paste your filters together with | as a separator:

dfilter <- df1[grep(paste0(filter1, collapse = "|"), df1$type),]

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