.spl_context within analysis and split functions

.spl_context is an optional parameter for any of rtables' special functions, i.e. afun (analysis function in analyze()), cfun (content or label function in summarize_row_groups()), or split_fun (e.g. for split_rows_by()).

Details

The .spl_context data.frame gives information about the subsets of data corresponding to the splits within which the current analyze action is nested. Taken together, these correspond to the path that the resulting (set of) rows the analysis function is creating, although the information is in a slightly different form. Each split (which correspond to groups of rows in the resulting table), as well as the initial 'root' "split", is represented via the following columns:

split: The name of the split (often the variable being split).
value: The string representation of the value at that split (split).
full_parent_df: A data.frame containing the full data (i.e. across all columns) corresponding to the path defined by the combination of split and value of this row and all rows above this row.
all_cols_n: The number of observations corresponding to the row grouping (union of all columns).
column for each column in the table structure (row-split and analyze contexts only): These list columns (named the same as names(col_exprs(tab))) contain logical vectors corresponding to the subset of this row's full_parent_df corresponding to the column.
cur_col_id: Identifier of the current column. This may be an internal name, constructed by pasting the column path together.
cur_col_subset: List column containing logical vectors indicating the subset of this row's full_parent_df for the column currently being created by the analysis function.
cur_col_expr: List of current column expression. This may be used to filter .alt_df_row, or any external data, by column. Filtering .alt_df_row by columns produces .alt_df.
cur_col_n: Integer column containing the observation counts for that split.
cur_col_split: Current column split names. This is recovered from the current column path.
cur_col_split_val: Current column split values. This is recovered from the current column path.

Note

Within analysis functions that accept .spl_context, the all_cols_n and cur_col_n columns of the data frame will contain the 'true' observation counts corresponding to the row-group and row-group x column subsets of the data. These numbers will not, and currently cannot, reflect alternate column observation counts provided by the alt_counts_df, col_counts or col_total arguments to build_table().