Upon creation of an informant object (with the create_informant() function), there are two sections containing properties: (1) 'table' and (2) 'columns'. The 'columns' section is initialized with the table's column names and their types (as _type). Beyond that, it is useful to provide details about the nature of each column and we can do that with the info_columns() function. A single column (or multiple columns) is targeted, and then a series of named arguments (in the form entry_name = "The *info text*.") serves as additional information for the column or columns.

info_columns(x, columns, ..., .add = TRUE)

Arguments

x An informant object of class ptblank_informant. The column or set of columns to focus on. Can be defined as a column name in quotes (e.g., ""), one or more column names in vars() (e.g., vars()), or with a select helper (e.g., starts_with("date")). Information entries as a series of named arguments. The names refer to subsection titles within COLUMN -> and the RHS contains the info text (informational text that can be written as Markdown and further styled with Text Tricks). Should new text be added to existing text? This is TRUE by default; setting to FALSE replaces any existing text for a property.

Value

A ptblank_informant object.

Details

The info text readily accepts Markdown formatting. Also, there are a few Text Tricks that are good to know. Markdown links written as < link url > or [ link text ]( link url ) will get nicely-styled links. Any dates expressed in the ISO-8601 standard with parentheses, "(2004-12-01)", will be styled with a font variation (monospaced) and underlined in purple. Spans of text can be converted to label text by using: (1) double parentheses around text for a rectangular label as in ((label text)), or (2) triple parentheses around text for a rounded-rectangular label like (((label text))). Finally, CSS styles can be applied to spans of info text with the following form:

[[ info text ]]<< CSS style rules >>

As an example of this in practice suppose you'd like to change the color of some text to red and make the font appear somewhat thinner. A variation on the following might be used:

"This is a [[factor]]<<color: red; font-weight: 300;>> value."

Function ID

3-2

# Create a pointblank informant # object with create_informant(); # we specify a read_fn with the # ~ followed by a statement that # gets the small_table dataset informant <- create_informant( read_fn = ~ small_table, tbl_name = "small_table", label = "An example." ) # The informant object has the 'table' # and 'columns' sections; we can add more # properties to individual columns in # the 'columns' section informant <- informant %>% info_columns( columns = vars(a), info = "In the range of 1 to 10. (SIMPLE)" ) %>% info_columns( columns = starts_with("date"), info = "Time-based values (e.g., Sys.time())." ) %>% info_columns( columns = "date", info = "The date part of date_time. (CALC)" ) # Upon printing the informant object, we see # the additions made to the 'Columns' section # The informant object can be written to # a YAML file with the yaml_write() # function; then, information can # be directly edited or modified # yaml_write( # informant = informant, # filename = "informant.yml" # ) # The YAML file can then be read back # into an informant object with the # yaml_read_informant() function # informant <- # yaml_read_informant( # filename = "informant.yml" # )