Why does case_when not work when two conditions involve the same column?-CodePudding

I'm using case_when within dplyr to lookup values in different tables depending on the value in one of my columns. It works well for one argument (either of the arguments below on their own), but when I add a second argument involving the same column I get an error about:

'names' attribute [1] must be the same length as the vector [0]

Here's a small example of the data, and the script that produces the error:

library(lubridate)
directory <- structure(list(data_label = c("BufT.1", "CTID.1", "CTNM.1", "CTOw.1", 
"CTTL.1", "CpEP.1", "DATA.1", "DATA.2", "DATA.3", "DATA.4", "DATA.5", 
"DATA.6", "DATA.7", "DATA.8", "DATA.105", "DCHT.1", "DSam.1", 
"DySN.1", "Dye#.1", "DyeB.1", "DyeB.2", "DyeB.3", "DyeB.4", "DyeB.5", 
"DyeN.1", "DyeN.2", "DyeN.3", "DyeN.4", "DyeN.5", "DyeW.1", "DyeW.2", 
"DyeW.3", "DyeW.4", "DyeW.5", "EPVt.1", "EVNT.1", "EVNT.2", "EVNT.3", 
"EVNT.4", "GTyp.1", "HCFG.1", "HCFG.2", "HCFG.3", "HCFG.4", "InSc.1", 
"InVt.1", "LANE.1", "LIMS.1", "LNTD.1", "LsrP.1", "MCHN.1", "MODF.1", 
"MODL.1", "NAVG.1", "NLNE.1", "OfSc.1", "PSZE.1", "PTYP.1", "PXLB.1", 
"RGNm.1", "RGOw.1", "RMXV.1", "RMdN.1", "RMdV.1", "RMdX.1", "RPrN.1", 
"RPrV.1", "RUND.1", "RUND.2", "RUND.3", "RUND.4", "RUNT.1", "RUNT.2", 
"RUNT.3", "RUNT.4", "Rate.1", "RunN.1", "SCAN.1", "SMED.1", "SMLt.1", 
"SVER.1", "SVER.3", "SVER.4", "Satd.1", "Scal.1", "Scan.1", "SpNm.1", 
"TUBE.1", "Tmpr.1", "User.1"), abif_type = c("short array", "cString", 
"cString", "cString", "pString", "byte", "short array", "short array", 
"short array", "short array", "short array", "short array", "short array", 
"short array", "short array", "short", "short", "pString", "short", 
"char", "char", "char", "char", "char", "pString", "pString", 
"pString", "pString", "pString", "short", "short", "short", "short", 
"short", "long", "pString", "pString", "pString", "pString", 
"pString", "cString", "cString", "cString", "cString", "long", 
"long", "short", "pString", "short", "long", "pString", "pString", 
"char[4]", "short", "short", "long array", "long", "cString", 
"long", "cString", "cString", "cString", "cString", "cString", 
"char array", "cString", "cString", "date", "date", "date", "date", 
"time", "time", "time", "time", "user", "cString", "long", "pString", 
"pString", "pString", "pString", "pString", "long array", "float", 
"short", "pString", "pString", "long", "pString")), row.names = c(NA, 
-90L), class = "data.frame")


data.date <- structure(list(index = c("RUND.1", "RUND.2", "RUND.3", "RUND.4"
), date = structure(c(19234, 19234, 19234, 19234), class = "Date")), row.names = c(NA, 
-4L), class = c("tbl_df", "tbl", "data.frame"))

data.time <- structure(list(index = c("RUNT.1", "RUNT.2", "RUNT.3", "RUNT.4"
), time = new("Period", .Data = c(56, 47, 8, 48), year = c(0, 
                                                           0, 0, 0), month = c(0, 0, 0, 0), day = c(0, 0, 0, 0), hour = c(17, 
                                                                                                                          19, 18, 19), minute = c(48, 0, 19, 0)), hsecond = c(0L, 0L, 0L, 
                                                                                                                                                                              0L)), row.names = c(NA, -4L), class = c("tbl_df", "tbl", "data.frame"
                                                                                                                                                                              ))



library(dplyr)
results <- directory %>%
  mutate(value = case_when(
    abif_type == "date" ~ data.date$date[match(data_label, data.date$index)],
    abif_type == "time" ~ data.time$time[match(data_label, data.time$index)]))

CodePudding user response：

I've found an answer, borrowing from here: dplyr case_when throws error names' attribute [1] must be the same length as the vector [0]

The problem was the date and time need to be of the same class.

results <- directory %>%
    mutate(value = case_when(
      abif_type == "date" ~ as.character(data.date$date[match(data_label, data.date$index)]),
      abif_type == "time" ~ as.character(data.time$time[match(data_label, data.time$index)])))

CodePudding user response：

Did you see an error when trying to create the data.time dataframe?

data.time <- structure(list(index = c("RUNT.1", "RUNT.2", "RUNT.3", "RUNT.4"
  ), time = new("Period", .Data = c(56, 47, 8, 48), year = c(0, 
                                                             0, 0, 0), month = c(0, 0, 0, 0), day = c(0, 0, 0, 0), hour = c(17, 
                                                                                                                            19, 18, 19), minute = c(48, 0, 19, 0)), hsecond = c(0L, 0L, 0L, 
                                                                                                                                                                                0L)), row.names = c(NA, -4L), class = c("tbl_df", "tbl", "data.frame"
                                                                                                                                                                                ))
Error in getClass(Class, where = topenv(parent.frame())) : 
  “Period” is not a defined class