memisc with data.table

[ghost]

Since I am often working with surveys the memisc library looks very promising. I always work with data.table and there seems to be an issue however.

When I generate a codebook with memisc on a data.table, there is the following issue: when I type the name of the object (say, mtcars) an error is thrown, see code below.

    library(memisc)
    library(data.table)

    data(mtcars)
    setDT(mtcars, keep.rownames=  T)
    mtcars = within(mtcars, {

      description(vs) = "whatever"
      description(am) = "something unclear"
      description(carb) = "something different"
      wording(vs) = "this is going to be a long comment"

      labels(vs) = c(
        "many" = 1,
        "not so many" = 0
      )

      labels(carb) = c(
        "one" = 1,
        "two" = 2,
        "three" = 3
      )

      missing.values(carb) = c(4,6, 8)

    })

    codebook(mtcars) %>% show_html

    # annotation(mtcars) = "my long story"

    # if data.frame = error and annotation(mtcars) = "....text...." then message "Error in if (nzchar(nm.i)) { : argument is of length zero"
    # annotation(mtcars)

    # if data.table: throws error "Error in format.item(char.trunc(col), justify = justify, ...) : 
    # unused argument (justify = justify)
    mtcars


    > sessionInfo()
    R version 3.2.3 (2015-12-10)
    Platform: x86_64-pc-linux-gnu (64-bit)
    Running under: Ubuntu 15.04

    locale:
      [1] LC_CTYPE=en_US.UTF-8       LC_NUMERIC=C               LC_TIME=nl_NL.UTF-8        LC_COLLATE=en_US.UTF-8     LC_MONETARY=nl_NL.UTF-8    LC_MESSAGES=en_US.UTF-8    LC_PAPER=nl_NL.UTF-8       LC_NAME=C                  LC_ADDRESS=C              
    [10] LC_TELEPHONE=C             LC_MEASUREMENT=nl_NL.UTF-8 LC_IDENTIFICATION=C       

    attached base packages:
      [1] grid      stats     graphics  grDevices utils     datasets  methods   base     

    other attached packages:
      [1] Hmisc_3.17-0      ggplot2_2.0.0     Formula_1.2-1     survival_2.38-3   magrittr_1.5      DescTools_0.99.15 manipulate_1.0.1  memisc_0.99.3     MASS_7.3-44       lattice_0.20-33   data.table_1.9.7 

    loaded via a namespace (and not attached):
      [1] Rcpp_0.12.3         nloptr_1.0.4        RColorBrewer_1.1-2  plyr_1.8.3          tools_3.2.3         rpart_4.1-10        boot_1.3-17         lme4_1.1-9          nlme_3.1-122        gtable_0.1.2        mgcv_1.8-7          Matrix_1.2-2       
    [13] parallel_3.2.3      mvtnorm_1.0-3       SparseM_1.7         proto_0.3-10        gridExtra_2.0.0     cluster_2.0.3       MatrixModels_0.4-1  nnet_7.3-11         foreign_0.8-66      latticeExtra_0.6-26 minqa_1.2.4         car_2.0-25         
    [25] scales_0.3.0        splines_3.2.3       rsconnect_0.4.1.11  pbkrtest_0.4-2      colorspace_1.2-6    quantreg_5.19       acepack_1.3-3.3     munsell_0.4.2       chron_2.3-47       

[melff]

You are using annotation etc. in a way they are not intended:

• annotation etc. are supposed only to work with objects of class "item" which are expected to be in a "data.set" object rather than a "data.frame" or "data.table" object.
• There is no support for "data.table" objects yet.

To get what you apparently want, try:

library(memisc)
library(data.table)

data(mtcars)
## This is necessary to get things working ...
mtcars <- as.data.set(mtcars)

mtcars <- within(mtcars, {

  description(vs) <- "whatever"
  description(am) <- "something unclear"
  description(carb) <- "something different"
  wording(vs) <- "this is going to be a long comment"

  labels(vs) <- c(
    "many" = 1,
    "not so many" = 0
  )

  labels(carb) <- c(
    "one" = 1,
    "two" = 2,
    "three" = 3
  )

  missing.values(carb) <- c(4,6, 8)
})

codebook(mtcars) 
annotation(mtcars) <- "my long story"
annotation(mtcars)
mtcars

## To get a data frame, use
# as.data.frame(mtcars)