List variables required by a pre-data table layout

Usage

vars_in_layout(lyt)

# S4 method for PreDataTableLayouts
vars_in_layout(lyt)

# S4 method for PreDataAxisLayout
vars_in_layout(lyt)

# S4 method for SplitVector
vars_in_layout(lyt)

# S4 method for Split
vars_in_layout(lyt)

# S4 method for CompoundSplit
vars_in_layout(lyt)

# S4 method for ManualSplit
vars_in_layout(lyt)

Arguments

lyt

(PreDataTableLayouts)
the layout (or a component thereof).

Value

A character vector containing the unique variables explicitly used in the layout (see the notes below).

Details

This will walk the layout declaration and return a vector of the names of the unique variables that are used in any of the following ways:

• Variable being split on (directly or via cuts)

• Element of a Multi-variable column split

• Content variable

• Value-label variable

Note

• This function will not detect dependencies implicit in analysis or summary functions which accept x or df and then rely on the existence of particular variables not being split on/analyzed.

• The order these variable names appear within the return vector is undefined and should not be relied upon.

Examples

lyt <- basic_table() %>%
  split_cols_by("ARM") %>%
  split_cols_by("SEX") %>%
  summarize_row_groups(label_fstr = "Overall (N)") %>%
  split_rows_by("RACE",
    split_label = "Ethnicity", labels_var = "ethn_lab",
    split_fun = drop_split_levels
  ) %>%
  summarize_row_groups("RACE", label_fstr = "%s (n)") %>%
  analyze("AGE", var_labels = "Age", afun = mean, format = "xx.xx")

vars_in_layout(lyt)
#> [1] "ARM"      "SEX"      "RACE"     "ethn_lab" "AGE"