samba: Mutate new columns

In romainfrancois/dance: Tibble Dancing

Description

Applies the ballet() and makes sure each result have the same vctrs::vec_size() as the number of elements in each group.

Usage

salsa(.tbl, ..., .env = caller_env())

chacha(.tbl)

samba(.tbl, ..., .env = caller_env())

madison(.tbl, ..., .name = "data", .env = caller_env())

Arguments

.tbl	A data frame, most likely a grouped data frame
..., .env	formulas for each column to create, and parent environment, see ballet()
.name	Name of the packed column made by charleston() The four functions play a separate role around the idea of dplyr::mutate(): chacha() reorganizes the rows of a grouped data frame so that data for each group is contiguous in each column. salsa() runs the ballet() defined by ... and makes sure the vctrs::vec_size() of each result is equal to the number of elements in that group. The result tibble of salsa() does not contain the grouping variables, just those columns specified by the .... samba() is the closest to dplyr::mutate(), it column binds the result of chacha() and salsa() with vctrs::vec_cbind(). madison() is similar to sambda() but the results are packed instead of being [vctrs::vec_cbind()]. The name of the created packed column is controled by the .name argument.

Examples

g <- group_by(iris, Species)

# Creates a `dance_grouped_df` tibble,
# which is the same as `g` but guarantees that the data for each column
# is contiguous within groups
chacha(g)

# returns a tibble of two columns
g %>%
  salsa(
    Sepal = ~Sepal.Length * Sepal.Width,
    Petal = ~Petal.Length * Petal.Width
  )

# returns a dance_grouped_df with the two
# additional columns `Sepal` and `Petal`
g %>%
  samba(
    Sepal = ~Sepal.Length * Sepal.Width,
    Petal = ~Petal.Length * Petal.Width
  )

# returns a dance_grouped_df with the one
# additional data frame column
g %>%
  madison(
    Sepal = ~Sepal.Length * Sepal.Width,
    Petal = ~Petal.Length * Petal.Width
  )

romainfrancois/dance documentation built on Nov. 21, 2019, 11:49 a.m.