Arithmetic operators for odcr classes

These arithmetic operators perform arithmetic on two objects of the same class, shape and dimensions.

# S3 method for xarray.core.dataarray.DataArray
+(xds, yds)

# S3 method for xarray.core.dataarray.DataArray
-(xds, yds)

# S3 method for xarray.core.dataarray.DataArray
/(xds, yds)

# S3 method for xarray.core.dataarray.DataArray
*(xds, yds)

Arguments

xds	xarray object
yds	xarray object

Value

An xarray object of same class, shape and dimensions as the inputs to the operator, holding the result.

Examples

if (FALSE) {
library(odcr)

# connect to a database, store the Daatcube connection internally (default and recommended)
database_connect(app = "Sentinel_2")

# build a query list
lat <- 22.821
lon <- 28.518
buffer <- 0.05

query <- list(
  'time' = c('2020-01', '2020-03'),
  'x' = c(lon - buffer, lon + buffer),
  'y' = c(lat + buffer, lat - buffer),
  'output_crs' = 'epsg:6933',
  'resolution' = c(-20,20)
)

# load data and return an xarray object for a query
ds <- dc_load(query = c(product = "s2_l2a", dask_chunks = dict(), query))

ndvi <- (ds[["nir"]] - ds[["red"]]) / (ds[["nir"]] + ds[["red"]])
ndvi

}