Using gsub to extract character string before white space in R -

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i have list of birthdays this:

dob <- c("9/9/43 12:00 am/pm", "9/17/88 12:00 am/pm", "11/21/48 12:00 am/pm")

i want grab calendar date variable (ie drop after first occurrence of white-space).

here's have tried far:

dob.abridged <- substring(dob,1,8) dob [1] "9/9/43 1" "9/17/88 " "11/21/48" dob.abridged <- gsub(" $","", dob.abridged, perl=t) > dob.abridged [1] "9/9/43 1" "9/17/88"  "11/21/48"

so code works calendar dates of length 6 or 7, not length 8. pointers on more effective regex use gsub can handle calendar dates of length 6, 7 or 8?

thank you.

no need substring, use gsub: 

gsub( " .*$", "", dob ) # [1] "9/9/43"   "9/17/88"  "11/21/48"

a space (), character (.) number of times (*) until end of string ($). see ?regex learn regular expressions.


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