Use of perl = TRUE

[Kyle Haynes]

Hi Howard,

Thanks for the package.

Have you ever considered the use of the perl = TRUE argument in a lot of your gsub() functions?

It offers considerable time benefits.

Below is an example having updated the nysiis_original function.

# install.packages("babynames")
# install.packages("phonics")
library("babynames")
library("phonics")

name <- babynames$name

length(name)
# 1858689

system.time(a <- nysiis_original_perl(name))
# user  system elapsed 
# 13.36    0.14   13.54 

system.time(b <- nysiis(name))
#  user  system elapsed 
# 22.75    0.24   23.02 

# All equal?
all.equal(a, b)
# [1] TRUE

# microbenchmark'ing
microbenchmark(
  nysiis_original_perl(name),
  nysiis(name), times = 25
)
# Unit: milliseconds
#                        expr      min       lq     mean   median       uq      max neval
#  nysiis_original_perl(name) 308.5931 311.0220 316.0347 312.2456 315.8408 345.8459    25
#                nysiis(name) 568.2662 573.1073 577.4318 575.4571 577.5975 606.7362    25

sessionInfo()
# R version 3.5.0 (2018-04-23)
# Platform: x86_64-w64-mingw32/x64 (64-bit)
# Running under: Windows 10 x64 (build 17763)
# 
# Matrix products: default
# 
# locale:
# [1] LC_COLLATE=English_Australia.1252  LC_CTYPE=English_Australia.1252    LC_MONETARY=English_Australia.1252 LC_NUMERIC=C                       LC_TIME=English_Australia.1252    
# 
# attached base packages:
# [1] stats     graphics  grDevices utils     datasets  methods   base     
# 
# other attached packages:
# [1] phonics_1.1.0   babynames_0.3.0
# 
# loaded via a namespace (and not attached):
# [1] compiler_3.5.0 tools_3.5.0    pillar_1.3.1   tibble_1.4.2   Rcpp_1.0.0     crayon_1.3.4   rlang_0.3.0.1 


# nysiis_original with perl = TRUE ...
nysiis_original_perl <- function(word, maxCodeLen = 6) {

    ## First, remove any nonalphabetical characters and capitalize it
    word <- gsub("[^[:alpha:]]*", "", word, perl = TRUE)
    word <- toupper(word)

    ## Translate first characters of name: MAC to MCC, KN to N, K to C, PH,
    ## PF to FF, SCH to SSS
    word <- gsub("^MAC", "MCC", word, perl = TRUE)
    word <- gsub("KN", "NN", word, perl = TRUE)
    word <- gsub("K", "C", word, perl = TRUE)
    word <- gsub("^PF", "FF", word, perl = TRUE)
    word <- gsub("PH", "FF", word, perl = TRUE)
    word <- gsub("SCH", "SSS", word, perl = TRUE)

    ## Translate last characters of name: EE to Y, IE to Y, DT, RT, RD,
    ## NT, ND to D
    word <- gsub("EE$", "Y", word, perl = TRUE)
    word <- gsub("IE$", "Y", word, perl = TRUE)
    word <- gsub("DT$", "D", word, perl = TRUE)
    word <- gsub("RT$", "D", word, perl = TRUE)
    word <- gsub("RD$", "D", word, perl = TRUE)
    word <- gsub("NT$", "D", word, perl = TRUE)
    word <- gsub("ND$", "D", word, perl = TRUE)

    ## First character of key = first character of name.
    first <- substr(word, 1, 1)
    word <- substr(word, 2, nchar(word))

    ## EV to AF else A, E, I, O, U to A
    word <- gsub("EV", "AF", word, perl = TRUE)
    word <- gsub("E|I|O|U", "A", word, perl = TRUE)

    ## Q to G, Z to S, M to N
    word <- gsub("Q", "G", word, perl = TRUE)
    word <- gsub("Z", "S", word, perl = TRUE)
    word <- gsub("M", "N", word, perl = TRUE)

    ## KN to N else K to C
    ## SCH to SSS, PH to FF
    ## Rules are implemented as part of opening block

    ## H to If previous or next is non-vowel, previous.
    word <- gsub("([^AEIOU])H", "\\1", word, perl = TRUE)
    word <- gsub("(.)H[^AEIOU]", "\\1", word, perl = TRUE)

    ## W to If previous is vowel, A
    word <- gsub("([AEIOU])W", "A", word, perl = TRUE)

    ## If last character is S, remove it
    word <- gsub("S$", "", word, perl = TRUE)

    ## If last characters are AY, replace with Y
    word <- gsub("AY$", "Y", word, perl = TRUE)

    ## Remove duplicate consecutive characters
    word <- gsub("([A-Z])\\1+", "\\1", word, perl = TRUE)

    ## If last character is A, remove it
    word <- gsub("A$", "", word, perl = TRUE)

    ## Append word except for first character to first
    word <- paste(first, word, sep = "")

    ## Truncate to requested length
    word <- substr(word, 1, maxCodeLen)

    return(word)
}

[James Howard]

Submit a pull request :)

[James Howard]

Closed with pull request #22.