# Methods common to all dataframes

The dataframe object is used for R data.frame objects that are managed by lazyNut. A data frame with lazyNut object name may be accessed in R through `eN["object_name"]` . An S4 class manages the relationship on the R side.

## description

    some_df description

The description of some_df will have additional elements: `File name` if there is an associated file (name) for the data frame; `rows`, the number of rows; and `columns`, the number of columns.

## load

    some_df load filename...

The file `filename` is loaded into the dataframe, assuming “eNd” ragged array file format. This may trigger subtype-specific processing.

## copy

    some_df copy source_df

Create a “sliced” copy of `some_df` that is named `source_df`. Only the data is copied, the subtype and any subtype-specific properties are “sliced” off.

## clone

    some_df clone source_df

Create a “deep” copy of `some_df` that is named `source_df`. Both data and facet information are copied, insofar as this is sensible.

## save_csv

    some_df save_csv filename...

Saves `some_df` using R write.csv to `filename`.

## load_csv

    some_df load_csv filename...

Loads into `some_df` using R read.csv from `filename`. Subtype-specific load-time processing will occur.

## get

    some_df get row_spec col_spec

Emit the elements of the dataframe `some_df` indicated by the row and column specifications `row_spec` and `col_spec`, which are in a format like 1-5,7-9.

    some_df get

Emit the whole dataframe `some_df` in a format similar to HTML, with additional tags indicating the type of each element.

## clear

    some_df clear

Erase all data in the data frame `some_df`. The subtype is not cleared.

## get_colnames

    some_df get_colnames

List the column names of the dataframe `some_df`.

## get_colname_dimensions

    some_df get_colname_dimensions

List the column names of the dataframe `some_df`, omitting the time column, and removing any common prefix among the remaining names.

## get_colnames_table

    some_df get_colnames_table

Emit the column names only of the dataframe `some_df` in the same format as `get`.

## get_colwise

    some_df get_colwise

Emit the dataframe `some_df` in a transposed format. The TBODY tag is replaced with TCBODY; the TR tag with TC; and the TC element carries a type attribute, rather than each element having a typing tag.

## get_column_as_list

    some_df get_column_as_list colname

Emit the elements of the column with heading `colname` of the dataframe `some_df` in a simple list without special table tags.

## for_each_row

    some_df for_each_row any_command...

Iterate over the rows of `some_df`. On each iteration, set a local macro variable with the name of the column element with a value of the corresponding cell, and execute `any_command`.