gdalcubes/man/as_json.Rd

36 lines
1.4 KiB
R

% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/cube.R
\name{as_json}
\alias{as_json}
\title{Query data cube properties}
\usage{
as_json(obj, file = NULL)
}
\arguments{
\item{obj}{a data cube proxy object (class cube)}
\item{file}{optional output file}
}
\value{
If file is NULL, the function returns a JSON string representing a graph that can be used to recreate the same
chain of gdalcubes operations even in a different R sessions.
}
\description{
gdalcubes internally uses a graph to serialize data cubes (including chained operations on cubes). This function derives a JSON
representation, which can be used to save data cube objects without pixel data to disk.
}
\examples{
# create image collection from example Landsat data only
# if not already done in other examples
if (!file.exists(file.path(tempdir(), "L8.db"))) {
L8_files <- list.files(system.file("L8NY18", package = "gdalcubes"),
".TIF", recursive = TRUE, full.names = TRUE)
create_image_collection(L8_files, "L8_L1TP", file.path(tempdir(), "L8.db"), quiet = TRUE)
}
L8.col = image_collection(file.path(tempdir(), "L8.db"))
v = cube_view(extent=list(left=388941.2, right=766552.4,
bottom=4345299, top=4744931, t0="2018-04", t1="2018-04"),
srs="EPSG:32618", nx = 497, ny=526, dt="P1M")
cat(as_json(select_bands(raster_cube(L8.col, v), c("B04", "B05"))))
}