# dataframe_subset_impl

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.

# set_df

    some_dfm set_df x_dataframe

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

Setting name: x

# set_select_from

    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

# set_values

    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