Bioequivalence and Bioavailability Forum

Know the month abbreviations [🇷 for BE/BA]

posted by Helmut  – Vienna, Austria, 2025-11-13 13:45 (216 d 11:43 ago) – Posting: # 24496
Views: 2,445

Hi ElMaestro,

❝ Well, some degree of sanity is part of my general goals. But obviously, in that case I should not have gone into bioequivalence to start with.

❝ […] a csv file with dates like "03/Apr/2024" …

❝ The solution I see is to translate every month abbrev in the data to the corresponding month abbrev of my locale and only then can it be sorted. Same thing if I convert the month abbrev to integer. Both options are equally viable. Clumsy, but I will get there.

Do you import the data with read.csv()? I would suggest read.table() instead. Then you can makes sure the ugly column is read as characters and it’s easy to split it into day, month, year, and convert to an ISO-date.

months <- function(lang = "en") {
  if (!lang %in% c("en", "at", "de", "da", "fr"))
    stop ("language \"", lang, "\" not implemented.")
  switch(lang,
    "en" = setNames(1:12, month.abb),
    "at" = setNames(1:12, c("Jän", "Feb", "Mär", "Apr", "Mai", "Jun",
                            "Jul", "Aug", "Sep", "Okt", "Nov", "Dec")),
    "de" = setNames(1:12, c("Jan", "Feb", "Mrz", "Apr", "Mai", "Jun",
                            "Jul", "Aug", "Sep", "Okt", "Nov", "Dec")),
    "da" = setNames(1:12, c("jan", "feb", "mar", "apr", "maj", "jun",
                            "jul", "aug", "sep", "okt", "nov", "dec")),
    "fr" = setNames(1:12, c("janv.", "févr.", "mars", "avr.", "mau", "juin",
                            "juil.", "août", "sept.", "oct.", "nov.", "déc.")))
}
iso.date <- function(lang = "en", datum, sep = "/") {
  if (!lang %in% c("en", "at", "de", "da", "fr"))
    stop ("language \"", lang, "\" not implemented.")
  sep.locs <- gregexec(sep, datum, perl = TRUE)[[1]][1, ]
  if (!length(sep.locs) == 2)
    stop ("sep \"", sep, "\" must occur exactly twice in each date.")
  d <- substr(datum, 1, sep.locs[1] - 1)
  m <- substr(datum, sep.locs[1] + 1, sep.locs[2] - 1)
  m <- sprintf("%02d", which(names(months(lang)) == m))
  y <- substr(datum, sep.locs[2] + 1, nchar(datum))
  paste0(y, "-", m, "-", d)
}
# Example with random dates
set.seed(123456)
days    <- 7
mons    <- 6
day     <- sprintf("%02d", round(runif(days, 1, 28), 0))
month   <- round(runif(mons, 1, 12))
en.date <- paste0(day, "/", names(months("en")[month]), "/", "2025")
de.date <- paste0(day, "/", names(months("de")[month]), "/", "2025")
da.date <- paste0(day, "/", names(months("da")[month]), "/", "2025")
fr.date <- paste0(day, "/", names(months("fr")[month]), "/", "2025")
dates   <- data.frame(lang = rep(c("en", "de", "da", "fr"), each = days),
                      date = c(en.date, de.date, da.date, fr.date), iso = NA)
for (j in 1:nrow(dates)) {
 dates$iso[j] <- iso.date(lang = dates$lang[j], dates$date[j])
}
dates$iso <- as.Date(dates$iso, format = "%F")
str(dates); print(dates[with(dates, order(lang, iso)), ], row.names = FALSE, right = FALSE)

'data.frame':   28 obs. of  3 variables:
 $ lang: chr  "en" "en" "en" "en" ...
 $ date: chr  "23/Feb/2025" "21/Dec/2025" "12/Mar/2025" "10/Oct/2025" ...
 $ iso : Date, format: "2025-02-23" "2025-12-21" ...
 lang date          iso       
 da   15/feb/2025   2025-02-15
 da   23/feb/2025   2025-02-23
 da   12/mar/2025   2025-03-12
 da   11/aug/2025   2025-08-11
 da   10/okt/2025   2025-10-10
 da   06/nov/2025   2025-11-06
 da   21/dec/2025   2025-12-21
 de   15/Feb/2025   2025-02-15
 de   23/Feb/2025   2025-02-23
 de   12/Mrz/2025   2025-03-12
 de   11/Aug/2025   2025-08-11
 de   10/Okt/2025   2025-10-10
 de   06/Nov/2025   2025-11-06
 de   21/Dec/2025   2025-12-21
 en   15/Feb/2025   2025-02-15
 en   23/Feb/2025   2025-02-23
 en   12/Mar/2025   2025-03-12
 en   11/Aug/2025   2025-08-11
 en   10/Oct/2025   2025-10-10
 en   06/Nov/2025   2025-11-06
 en   21/Dec/2025   2025-12-21
 fr   15/févr./2025 2025-02-15
 fr   23/févr./2025 2025-02-23
 fr   12/mars/2025  2025-03-12
 fr   11/août/2025  2025-08-11
 fr   10/oct./2025  2025-10-10
 fr   06/nov./2025  2025-11-06
 fr   21/déc./2025  2025-12-21

—
Dif-tor heh smusma 🖖🏼 Довге життя Україна! 
Helmut Schütz


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Complete thread:

• September trouble ElMaestro 2025-11-10 12:26 [🇷 for BE/BA] 
  • September trouble mittyri 2025-11-10 20:38
  • More months trouble Helmut 2025-11-11 09:37
    • More months trouble ElMaestro 2025-11-13 05:20
      • Know the month abbreviationsHelmut 2025-11-13 12:45
        • Know the month abbreviations ElMaestro 2025-11-14 16:34
  • Worse in France Ohlbe 2025-11-12 15:13
    • Worse in France ElMaestro 2025-11-14 16:38