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booleanR

Complex boolean string match functions for R:

bool_detect is more elegant code and slightly quicker but possibly buggy. bool_detect2 is older and tested, and supports word-wise regex matching.

bool_detect = function(x, qry, ignore_case = TRUE,
    print_call = FALSE){...}

bool_detect2 = function(x, qry, ignore_case = TRUE, in_word = TRUE,
    print_call = FALSE){...}
  • x - a character string or vector of texts to search
  • qry - a character string boolean search term
  • ignore_case - ignore case when matching
  • in_word - Wildcard matching only within whole word (FALSE matches across whole document)
  • print_call - Print the final command call to console

bool_filter_db is a filter function compatible with dplyr's remote connectivity (database) functionality. It currently doesn't support in-piping (db_tbl %>% bool_filter_db(...) will fail)

bool_filter_db = function(db_tbl, col, qry, print_call=FALSE){...}
  • db_tbl - a remote data table object - e.g. created with tbl(con, "mytable")
  • col - name of volumn of db_tbl to query (string)
  • qry - a character string boolean search term

Examples

x = "The quick fox jumps over the lazy dog"

bool_detect(x, 'dog')
bool_detect(x, 'bird')
bool_detect(x, 'dog OR bird')
bool_detect(x, 'dog AND bird')
bool_detect(x, 'dog & (fox | cat)')
bool_detect(x, '"lazy fox"')
bool_detect(x, "fox AND 'lazy dog'")
bool_detect(x, "('pretty poly' OR bird) OR (quick AND (squirrel OR fox))")
bool_detect(x, "f?x")
bool_detect2(x, 'fox*lazy', in_word = F)
bool_detect2(x, 'fox*lazy', in_word = T)
bool_detect2(x, '"fox * lazy"', in_word = F)
bool_detect2(x, '"fox * lazy"', in_word = T)
bool_detect(x, '"fox " AND " lazy"')
bool_detect(x, "fox AND -'fox cubs'", print_call=T)
bool_detect(c(x,x,x), 'dog')

remote database filtering

require(RPostgreSQL)

drv <- dbDriver("PostgreSQL")
con <- dbConnect(drv, dbname = "my_database", host = "localhost",
                 port = 5432, user = "myusername")

copy_to(con, iris, "iris", temporary=F, indexes = list(names(iris)))

iris_pg <- tbl(con, "iris")

set_vir <- bool_filter_db(iris_pg, 'Species', 'setosa OR virginica')

# inspect generated SQL
show_query(set_vir)

# action query and retrieve data
set_vir %>% collect()

Dependencies

  • stringr
  • stringi
  • dplyr