Determine if a character string "starts with" with the specified characters.
Determine if a character string "starts with" with the specified characters.
startsWith(str, pattern, trim=FALSE, ignore.case=FALSE)
str |
character vector to test |
pattern |
characters to check for |
trim |
Logical flag indicating whether leading whitespace should
be removed from |
ignore.case |
Logical flag indicating whether case should be ignored when testing for a match. |
This function returns TRUE for each element of the vector str
where pattern occurs at the beginning of the string. If
trim is TRUE, leading whitespace is removed from the elements
of str before the test is performed. If ignore.case is
TRUE, character case is ignored.
Boolean vector of the same length as str.
Gregory R. Warnes greg@warnes.net
## simplest example:
startsWith( 'Testing', 'Test')
## vector examples
s <- c('Testing', ' Testing', 'testing', 'Texting')
names(s) <- s
startsWith(s, 'Test') # ' Testing', 'testing', and 'Texting' do not match
startsWith(s, 'Test', trim=TRUE) # Now ' Testing' matches
startsWith(s, 'Test', ignore.case=TRUE) # Now 'testing' matchesPlease choose more modern alternatives, such as Google Chrome or Mozilla Firefox.