Convert a qgis_result object or one of its elements to a stars object

Convert a qgis_result object or one of its elements to a stars object

Usage

# S3 method for class 'qgis_outputRaster'
st_as_stars(x, ...)

# S3 method for class 'qgis_outputLayer'
st_as_stars(x, ...)

# S3 method for class 'qgis_result'
st_as_stars(x, ...)

Arguments

x

A qgis_result object from qgis_run_algorithm() or a qgis_output* object from one of the qgis_extract_output() functions.

...

Arguments passed to stars::read_stars().

Value

A stars or a stars_proxy object.

Details

The stars package must be loaded explicitly to use these methods.

See also

Other topics about coercing processing output: qgis_as_raster(), qgis_as_terra(), st_as_sf

Other topics about accessing or managing processing results: qgis_as_raster(), qgis_as_terra(), qgis_clean_result(), qgis_extract_output(), qgis_result_status(), st_as_sf

Examples

# \donttest{
# not running below examples in R CMD check to save time
result <- qgis_run_algorithm(
  "native:slope",
  INPUT = system.file("longlake/longlake_depth.tif", package = "qgisprocess")
)
#> Argument `Z_FACTOR` is unspecified (using QGIS default value).
#> Using `OUTPUT = qgis_tmp_raster()`

# most direct approach, autoselecting a `qgis_outputRaster` type
# output from the `result` object and reading as stars or stars_proxy:
stars::st_as_stars(result)
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>                              Min.   1st Qu.    Median      Mean   3rd Qu.
#> file2b045445b2e4.tif  0.008276554 0.2864364 0.4271587 0.4269891 0.5803983
#>                            Max. NA's
#> file2b045445b2e4.tif  0.8075118 6475
#> dimension(s):
#>   from  to  offset  delta               refsys point x/y
#> x    1 100  409940  18.27 NAD83 / UTM zone 20N FALSE [x]
#> y    1 100 5084861 -15.54 NAD83 / UTM zone 20N FALSE [y]
stars::st_as_stars(result, proxy = TRUE)
#> stars_proxy object with 1 attribute in 1 file(s):
#> $file2b045445b2e4.tif
#> [1] "[...]/file2b045445b2e4.tif"
#> 
#> dimension(s):
#>   from  to  offset  delta               refsys point x/y
#> x    1 100  409940  18.27 NAD83 / UTM zone 20N FALSE [x]
#> y    1 100 5084861 -15.54 NAD83 / UTM zone 20N FALSE [y]

# if you need more control, extract the needed output element first:
output_raster <- qgis_extract_output(result, "OUTPUT")
stars::st_as_stars(output_raster)
#> stars object with 2 dimensions and 1 attribute
#> attribute(s):
#>                              Min.   1st Qu.    Median      Mean   3rd Qu.
#> file2b045445b2e4.tif  0.008276554 0.2864364 0.4271587 0.4269891 0.5803983
#>                            Max. NA's
#> file2b045445b2e4.tif  0.8075118 6475
#> dimension(s):
#>   from  to  offset  delta               refsys point x/y
#> x    1 100  409940  18.27 NAD83 / UTM zone 20N FALSE [x]
#> y    1 100 5084861 -15.54 NAD83 / UTM zone 20N FALSE [y]
# }