epi_clean_compare_str: Compare two strings

In AntonioJBT/episcout: Quickly Clean, Explore and Visualise Large Epidemiological Datasets

Description

Compare two strings and determine if one is substring of the other. epi_clean_compare_str() uses stringi::stri_detect(). Developed when comparing a database of observed and matched values for drug treatments from the BNF. Can be used generically as a light wrapper for stri_detect(). stri_detect() determines if there is at least one match to a corresponding pattern.

Usage

epi_clean_compare_str(df = NULL, row_n = 1, string_col = "",
  fixed_chr_col = "", ...)

Arguments

df	a data frame object containing rows with strings to compare
row_n	row number within the data frame with two columns to compare, default is 1
string_col	column number with value which will be passed to stri_detect as stri_detect(str = string, fixed = fixed_chr)
fixed_chr_col	column number value which will be passed to stri_detect as stri_detect(str = string, fixed = fixed_chr)
...	other options passed to stri_detect()

Value

returns the output of stri_detect(), a boolean TRUE/FALSE testing whether the value of fixed_chr_col is a sub-string of that in string_col

Note

fixed_chr_col and string_col are extracted as characters and compared as fixed characters, not with regex. The value in string_col will be the character vector with strings to search in.

Author(s)

Antonio Berlanga-Taylor <https://github.com/AntonioJBT/episcout>

See Also

stri_detect.

Examples

## Not run: 
test data:
letts <- paste(letters, collapse = ' ')
other_letts <- toupper(paste(letters, collapse = ' '))
df_comp <- data.frame ('sub' = rep(x = substr(letts, 1, 5), 10),
                       'str' = rep(x = substr(letts, 1, 5), 10),
                      stringsAsFactors = FALSE)
df2_comp <- data.frame ('sub' = rep(x = substr(letts, 1, 5), 10),
                        'str' = rep(x = substr(other_letts, 6, 10), 10),
                       stringsAsFactors = FALSE)
# Create a new data frame and rename columns:
df3 <- rbind(df_comp, df2_comp)
col_1 <- 'sub'
col_2 <- 'str'
val_id <- 1
# df3[val_id, c(col_1, col_2)]
# Should evaluate to TRUE:
epi_clean_compare_str(df3, val_id, col_1, col_2)

## End(Not run)

AntonioJBT/episcout documentation built on Nov. 7, 2019, 5:34 p.m.