R - test if first occurrence of string1 is followed by string2

Question

I have an R string  with the format  s      some letters and numbers   a number   more numbers  letters  punctuation  etc  anything      I simply want a way of checking if s contains   2  in the first position  In other words  after the first   symbol  is the single number a  2   How do I do this in R   I m assuming I need some complicated regex expresion   Examples   39820432 2 349802j 32hfh   TRUE   43lda821 9 428fj 2f   FALSE  notice there is a  2 there  but not in the right spot

User · Accepted Answer

gt  grepl         1  s   1  FALSE  gt  grepl         2  s   1  TRUE   basically  look for everything at the beginning except    and then the  2    1 to  Ananda Mahto for suggesting grepl instead of grep

User · Answer

I think it s worth answering the generic question  R - test if string contains string  here   For that  use the  grep function     example   gt  if length grep  ab   aacd    gt 0  print  found   else print  Not found    1   Not found   gt  if length grep  ab   abcd    gt 0  print  found   else print  Not found    1   found

[r] R - test if first occurrence of string1 is followed by string2

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