A dataframe whose value is a (row-wise) subset of another dataframes, in the sense of the “subset” command of “R”. The subset will be re-run as needed to reflect changes in the source dataframe; evaluation is lazy. The subset will be subset(eN["x_dataframe"],eval(parse(key_col))%in%key). Is a setting_user.

some_dfm set_df x_dataframe

Indicate that the x argument of the R “subset” command should be eN["x_dataframe"].

Setting name: x

some_dfn set_select_from key_col

Indicate that key_col is the column whose values should be consulted to determine which rows to include. Quotation marks are required if an R variable is not desired.

Setting name: x_column

some_dfn set_values key...

Indicate that rows that have the value key in the key column are those to be included. c() syntax around quotation-mark-enclosed strings, or a single quotation-mark-enclosed string is normally required.

Setting name: key