# NOT RUN {
file <- system.file("extdata", "temperature.nc", package = "metR")
# Get a list of variables.
variables <- GlanceNetCDF(file)
print(variables)
# The object returned by GlanceNetCDF is a list with lots
# of information
str(variables)
# Read only the first one, with name "var".
field <- ReadNetCDF(file, vars = c(var = names(variables$vars[1])))
# Add a new variable.
# <U+00A1>Make sure it's on the same exact grid!
field[, var2 := ReadNetCDF(file, out = "vector")]
# }
# NOT RUN {
if (!interactive())
# Using a DAP url
url <- "http://iridl.ldeo.columbia.edu/SOURCES/.Models/.SubX/.GMAO/.GEOS_V2p1/.hindcast/.ua/dods"
field <- ReadNetCDF(url, subset = list(M = 1,
P = 10,
S = "1999-01-01"))
# In this case, opening the netcdf file takes a non-neglible
# amount of time. So if you want to iterate over many dimensions,
# then it's more efficient to open the file first and then read it.
ncfile <- ncdf4::nc_open(url)
field <- ReadNetCDF(ncfile, subset = list(M = 1,
P = 10,
S = "1999-01-01"))
# }
# NOT RUN {
# }
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