Search notes:

R functions: tolower / toupper

tolower(vec) converts a character vector to lower case. toupper(vec) converts a character vector to upper case. 
txt <- c('Foo', 'bar, BAZ');

low  <- tolower(txt);
up   <- toupper(txt);

low;
#
#  [1] "foo"      "bar, baz"

up;
#
#  [1] "FOO"      "BAR, BAZ"
Github repository about-r, path: /functions/tolower-toupper.R

See also

Basic string manipulation
casefold()
Index to (some) R functions

Index

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