https://github.com/krlmlr/scalar
Scalars
https://github.com/krlmlr/scalar
r
Last synced: 3 months ago
JSON representation
Scalars
- Host: GitHub
- URL: https://github.com/krlmlr/scalar
- Owner: krlmlr
- Archived: true
- Created: 2019-10-27T17:34:36.000Z (about 6 years ago)
- Default Branch: master
- Last Pushed: 2019-10-27T17:34:52.000Z (about 6 years ago)
- Last Synced: 2024-12-04T09:40:05.180Z (11 months ago)
- Topics: r
- Language: R
- Size: 6.84 KB
- Stars: 1
- Watchers: 2
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.Rmd
Awesome Lists containing this project
- jimsghstars - krlmlr/scalar - Scalars (R)
README
---
output: github_document
---
```{r, include = FALSE}
knitr::opts_chunk$set(
collapse = TRUE,
comment = "#>",
fig.path = "man/figures/README-",
out.width = "100%"
)
library(tidyverse)
pkgload::load_all()
```
# scalar
[](https://www.tidyverse.org/lifecycle/#experimental)
The goal of scalar is to provide a [vctrs](https://vctrs.r-lib.org/) compatible way to indicate that a vector is intended to have length one.
## Installation
You can install the released version of scalar from [CRAN](https://CRAN.R-project.org) with:
``` r
install.packages("scalar")
```
## Example
This class is useful to distinguish between scalars and vectors when creating one-row tibbles that contain arbitrary objects, e.g. results of `rowwise()`-like computations.
```{r example}
library(scalar)
wrap_unless_scalar <- function(x) {
if (is_scalar(x)) return(x)
list(x)
}
tibble_row <- function(...) {
lst <- tibble::lst(...)
row <- purrr::map(lst, wrap_unless_scalar)
tibble(!!!row)
}
tibble_row(a = 1, b = 2:3, c = list(4))
tibble_row(a = scalar(1), b = 2:3, c = scalar(list(4)))
```
Non-scalars are rejected. Concatenation returns a "bare" object.
```{r example2, error = TRUE}
scalar(1:2)
vec_c(scalar(1), scalar(2))
```