[R] element wise pattern recognition and string substitution

[Jun Shen]

Dear list,

I have a vector of strings that cannot be described by one pattern. So
let's say I construct a vector of patterns in the same length as the vector
of strings, can I do the element wise pattern recognition and string
substitution.

For example,

pattern1 <- "([^.]*)\\.([^.]*\\.[^.]*)\\.(.*)"
pattern2 <- "([^.]*)\\.([^.]*)\\.(.*)"

patterns <- c(pattern1,pattern2)
strings <- c('TX.WT.CUT.mean','mg.tx.cv')

Say I want to extract "WT.CUT" from the first string and "tx" from the
second string. If I do

sub(patterns, '\\2', strings), only the first pattern will be used.

looping the patterns doesn't work the way I want. Appreciate any comments.
Thanks.

Jun

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