Nest SpatVector rows — nest.SpatVector • tidyterra

nest() creates list-columns of SpatVector objects.

Usage

# S3 method for class 'SpatVector'
nest(.data, ..., .by = NULL, .key = NULL, .names_sep = NULL)

Arguments

.data

A SpatVector.

...

<tidy-select> Columns to nest; these will appear in the inner data frames.

Specified using name-variable pairs of the form new_col = c(col1, col2, col3). The right hand side can be any valid tidyselect expression.

If not supplied, then ... is derived as all columns not selected by .by, and will use the column name from .key.

: previously you could write df |> nest(x, y, z). Convert to df |> nest(data = c(x, y, z)).

.by

<tidy-select> Columns to nest by; these will remain in the outer data frame.

.by can be used in place of or in conjunction with columns supplied through ....

If not supplied, then .by is derived as all columns not selected by ....

.key

The name of the resulting nested column. Only applicable when ... isn't specified, i.e. in the case of df |> nest(.by = x).

If NULL, then "data" will be used by default.

.names_sep

If NULL, the default, the inner names will come from the former outer names. If a string, the new inner names will use the outer names with names_sep automatically stripped. This makes names_sep roughly symmetric between nesting and unnesting.

Value

A tibble with one or more list-columns of SpatVector objects.

terra equivalent

terra::svc().

Methods

Implementation of the generic tidyr::nest() method.

`SpatVector`

The geometry column must be nested with the other attributes that form each nested SpatVector. These nested list-columns contain SpatVector objects and cannot be passed directly to tidyr::unnest().

Examples

v <- terra::vect(system.file("extdata/cyl.gpkg", package = "tidyterra"))

v |>
  group_by(cpro) |>
  nest()
#> # A tibble: 9 × 2
#> # Groups:   cpro [9]
#>   cpro  data          
#>   <chr> <list>        
#> 1 05    <SpatVctr[,2]>
#> 2 09    <SpatVctr[,2]>
#> 3 24    <SpatVctr[,2]>
#> 4 34    <SpatVctr[,2]>
#> 5 37    <SpatVctr[,2]>
#> 6 40    <SpatVctr[,2]>
#> 7 42    <SpatVctr[,2]>
#> 8 47    <SpatVctr[,2]>
#> 9 49    <SpatVctr[,2]>

# Convert to a named SpatVectorCollection.
nested <- nest(v, .by = cpro)

sv <- pull(nested, data)
names(sv) <- pull(nested, cpro)

terra::svc(sv)
#>  class       : SpatVectorCollection
#>  length      : 9
#>  geometry    : polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>                polygons (1)
#>  crs (first) : ETRS89-extended / LAEA Europe (EPSG:3035)
#>  names       : 05, 09, 24, 34, 37, 40, 42, 47, 49

Nest `SpatVector` rows