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R mapping

John Mount

2023-08-19

rqdatatable re-maps a number of symbols for data.table translation (for rquery/SQL re-mappings, please see here). For instance, please take note of the n() and rank() functions in the following code example.

library("rqdatatable")
library("wrapr")

dL <- build_frame(
  "subjectID", "surveyCategory"     , "assessmentTotal"|
    1          , "withdrawal behavior", 5              |
    1          , "positive re-framing", 2              |
    2          , "withdrawal behavior", 3              |
    2          , "positive re-framing", 4              |
    2          , "other"              , 0              )

scale <- 0.237
rquery_pipeline <- local_td(dL) %.>%
  extend_nse(.,
             probability :=
               exp(assessmentTotal * scale)/
               sum(exp(assessmentTotal * scale)),
             count := n(),
             rank := rank(),
             orderby = c("assessmentTotal", "surveyCategory"),
             reverse = c("assessmentTotal"),
             partitionby = 'subjectID')  %.>%
  orderby(., c("subjectID", "probability"))
res <- ex_data_table(rquery_pipeline, tables = list(dL = dL))
knitr::kable(res)

The common re-mappings are can be found in the package-private variable rqdatatable:::data_table_extend_fns.

str(rqdatatable:::data_table_extend_fns)

## List of 6
##  $ ngroup    :List of 2
##   ..$ data.table_version: chr ".GRP"
##   ..$ need_one_col      : logi TRUE
##  $ rank      :List of 2
##   ..$ data.table_version: chr "cumsum(rqdatatable_temp_one_col)"
##   ..$ need_one_col      : logi TRUE
##  $ row_number:List of 2
##   ..$ data.table_version: chr "cumsum(rqdatatable_temp_one_col)"
##   ..$ need_one_col      : logi TRUE
##  $ n         :List of 2
##   ..$ data.table_version: chr "sum(rqdatatable_temp_one_col)"
##   ..$ need_one_col      : logi TRUE
##  $ random    :List of 2
##   ..$ data.table_version: chr "runif(.N)"
##   ..$ need_one_col      : logi FALSE
##  $ rand      :List of 2
##   ..$ data.table_version: chr "runif(.N)"
##   ..$ need_one_col      : logi FALSE

The column rqdatatable_temp_one_col is introduced (and removed) from intermediate data frames as needed.

These mappings help allow the same operator pipeline to be used in R and in a database. For the database mappings please see here.

These binaries (installable software) and packages are in development.
They may not be fully stable and should be used with caution. We make no claims about them.