stars (version 0.2-0)

read_ncdf: read ncdf file into stars object

Description

Read data from a file using the NetCDF library directly.

Usage

read_ncdf(.x, ..., var = NULL, ncsub = NULL,
  curvilinear = character(0))

Arguments

.x

NetCDF file or source

...

ignored

var

variable name or names (they must be on matching grids)

ncsub

matrix of start, count columns

curvilinear

length two character vector with names of subdatasets holding longitude and latitude values for all raster cells.

Details

The following logic is applied to coordinate axes. If any coordinate axes have regularly spaced coordinates they are reduced to the offset/delta form with 'affine = c(0, 0)', otherwise the values of the coordinates are stored. If the data has two or more dimensions and the first two are regular they are nominated as the 'raster' for plotting.

If `var` is not set the first set of variables on a shared grid is used. It's supposed to be the grid with the most dimensions, but there's no control yet (see `ncmeta::nc_grids(.x)` for the current assumption).

start and count columns of ncsub must correspond to the variable dimemsion (nrows) and be valid index using `ncdf4::ncvar_get` convention (start is 1-based).

Examples

# NOT RUN {
f <- system.file("nc/reduced.nc", package = "stars")
read_ncdf(f)
read_ncdf(f, var = c("anom"))
read_ncdf(f, ncsub = cbind(start = c(1, 1, 1, 1), count = c(10, 12, 1, 1)))


# }