[R] language study notes --- String Processing

String

Text file reading

Use readLines()read



using scan()reading
wherein when a parameter sep="\n", the row read, what=specify the data type read

String concatenation

Using paste()function connection string

String split

Use strsplit()function split

returns a list, you can use the unlist()View

String search

Using the grep()function returns the index of the default


use of grepl()the function, the return value is a logical value

Using the regexpr()function
-1 indicates a mismatch, the match represents 1

using gregexpr()the function search
returns the matching of each element in a list

regexec()similar effect

String replacement

sub()Character function replaces the first match, the gsub()function replaces all occurrences of characters

String extraction

Use surstr()functions to extract , can be assigned directly