Add a generic comment to the dtrackr history graph

A comment can be any kind of note and is added once for every current grouping as defined by the .message field. It can be made context specific by including variables such as {.count} and {.total} in .message which refer to the grouped and ungrouped counts at this current stage of the pipeline respectively. It can also pull in any global variable.

Usage

comment(
  .data,
  .messages = .defaultMessage(),
  .headline = .defaultHeadline(),
  .type = "info",
  .asOffshoot = (.type == "exclusion"),
  .tag = NULL
)

Arguments

.data

a dataframe which may be grouped

.messages

a character vector of glue specifications. A glue specification can refer to any grouping variables of .data, or any variables defined in the calling environment, the {.total} of all rows, the {.count} variable which is the count in each group and {.strata} a description of the group

.headline

a glue specification which can refer to grouping variables of .data, or any variables defined in the calling environment, or the {.total} variable (which is nrow(.data)) and {.strata} which is a description of the grouping

.type

one of "info","...,"exclusion": used to define formatting

.asOffshoot

do you want this comment to be an offshoot of the main flow (default = FALSE).

.tag

if you want the summary data from this step in the future then give it a name with .tag.

Value

the same .data dataframe with the history graph updated with the comment

Examples

library(dplyr)
library(dtrackr)
iris %>% track() %>% comment("hello {.total} rows") %>% history()
#> dtrackr history:
#> number of flowchart steps: 2 (approx)
#> tags defined: <none>
#> items excluded so far: <not capturing exclusions>
#> last entry / entries:
#> └ "hello 150 rows"