Build a rowrecs_to_blocks() control table that specifies a un-pivot (or "shred").

Some discussion and examples can be found here: https://winvector.github.io/FluidData/FluidData.html and here https://github.com/WinVector/cdata.

build_unpivot_control(
  nameForNewKeyColumn,
  nameForNewValueColumn,
  columnsToTakeFrom,
  ...
)

Arguments

nameForNewKeyColumn	character name of column to write new keys in.
nameForNewValueColumn	character name of column to write new values in.
columnsToTakeFrom	character array names of columns to take values from.
...	not used, force later args to be by name

Value

control table

See also

rowrecs_to_blocks

Examples

build_unpivot_control("measurmentType", "measurmentValue", c("c1", "c2"))
#>   measurmentType measurmentValue
#> 1             c1              c1
#> 2             c2              c2