switch-ext: Switch with a list of parameters

In mark: Miscellaneous, Analytic R Kernels

Switch with a list of parameters

Description

switch_params() is a vectorized version of switch switch_case() uses a formula syntax to return the value to the right of the tilde (~) when x is TRUE switch_in_case() is a special case of switch_case() for match()-ing x in the values on the left to return the value on the right.

Usage

switch_params(x, ...)

switch_in_case(x, ..., .default = NULL, .envir = parent.frame())

switch_case(..., .default = NULL, .envir = parent.frame())

Arguments

x	A vector of values
...	Case evaluations (named for switch_params)
.default	The default value if no matches are found in ... (default: NULL produces an NA value derived from ...)
.envir	The environment in which to evaluate the LHS of ... (default: parent.frame())

Details

Switch with a list of params

Value

A named vector of values of same length x; or for switch_case, an unnamed vector of values matching the rhs of ...

Inspired from:

• https://stackoverflow.com/a/32835930/12126576

• https://github.com/tidyverse/dplyr/issues/5811

Examples

# by single
switch_params(c("j", "m", "b"), j = 10, b = 2, m = 13)


# match with TRUE
switch_case(
  1:10 == 9      ~ NA_integer_,
  1:10 %% 3 == 0 ~ 1:10,
  1:10 %% 4 == 0 ~ 11:20,
  1:10 %% 5 == 0 ~ 21:30,
  1:10 %% 2 == 0 ~ 31:40,
  .default = -1L
)

# match within a vector
switch_in_case(
  c(1, 2, 12, 4, 20, 21),
  1:10  ~ 1,
  11:20 ~ 2
)

switch_in_case(
  c("a", "b", "d", "e", "g", "j"),
  letters[1:3] ~ "a",
  letters[5:6] ~ "e"
)

use_these <- c(1, 3, 2, 5)
switch_in_case(
  1:10,
  use_these ~ TRUE,
  .default = FALSE
)

ne <- new.env()
ne$use_these2 <- use_these
# error
try(switch_in_case(
  1:10,
  use_these2 ~ TRUE
))
switch_in_case(
  1:10,
  use_these2 ~ TRUE,
  .envir = ne
)

switch_in_case(
  seq.int(1, 60, 6),
  1:10          ~ "a",
  11:20         ~ "b",
  c(22, 24, 26) ~ "c",
  30:Inf        ~ "d"
)

# Use functions
switch_in_case(
  1:6,
  c(1, 3, 5) ~ exp,
  c(2, 4) ~ log
)

mark documentation built on Oct. 23, 2023, 9:06 a.m.