griddap_split: Title Get ERDDAP gridded data restricted to a given season of...

In rerddapUtils: Miscellaneous Utilities for 'rerddap'

Title Get ERDDAP gridded data restricted to a given season of the year

Description

griddap_season uses the R program 'rerddap::griddap()' to extract environmental data from an 'ERDDAP' server in an (time, z, y ,x) bounding box where time is restricted to a given season of the year (see below). Arguments are the same as in 'rerddap::griddap()' except for the added 'season' parameter. 'read' and 'fmt' options are ignored.

Usage

griddap_split(
  datasetx,
  ...,
  fields = "all",
  stride = 1,
  request_split = NULL,
  fmt = "nc",
  url = rerddap::eurl(),
  store = rerddap::disk(),
  read = TRUE,
  callopts = list(),
  aggregate_file = NULL
)

Arguments

datasetx	Anything coercable to an object of class info. So the output of a call to info, or a datasetid, which will internally be passed through info
...	Dimension arguments. See examples. Can be any 1 or more of the dimensions for the particular dataset - and the dimensions vary by dataset. For each dimension, pass in a vector of length two, with min and max value desired. at least 1 required.
fields	(character) Fields to return, in a character vector.
stride	(integer) How many values to get. 1 = get every value, 2 = get every other value, etc. Default: 1 (i.e., get every value)
request_split	A numeric vector indicating the number of splits for each dimension, used to segment the request into manageable chunks. This is particularly useful for large datasets.
fmt	(character) One of: nc: save output to a netcdf file memory: save output in a dataframe in memory duckdb: save data in a duckdb database parquet: save data as a partitioned parquet dataset in a directory
url	A URL for an ERDDAP server. Default: https://upwell.pfeg.noaa.gov/erddap/ - See rerddap::eurl() for more information
store	ignored
read	ignored
callopts	Curl options passed on to verb-GET
aggregate_file	A string specifying: if is.null(aggregate_file) then a temporary file is created that does not overwrite user space if "fmt = nc" the path to the NetCDF file to store the results if "fmt = duckdb" the path to the duckdb file to store the results if "fmt = memory" the value is ignored

Value

Varies by format requested:

• if "fmt = nc" the path to the NetCDF file where the results are stored

• if "fmt = duckdb" the path to the duckdb file where the results are stored

• if "fmt = memory" the usual rerddap::griddap dataframe

Examples

myURL <- "https://coastwatch.pfeg.noaa.gov/erddap/"
response <- try(httr::HEAD(myURL, httr::timeout(20)), silent = TRUE)
if (inherits(response, "try-error")) {
  message("The ERDDAP\u2122 server is not responding")
} else
{
data(wind_info)
request_split <- list(time = 2, altitude = 1, latitude = 1, longitude = 1)
res <- try(griddap_split(wind_info,
                     time = c('2015-12-31','2016-01-01'),
                     latitude = c(20, 21),
                     longitude = c(220, 221),
                     fields = 'mod_current',
                     request_split = request_split
                     ), silent = TRUE)
if (inherits(res, "try-error")) {
   message("Unable to retrieve data from the ERDDAP\u2122 server")
   }
}

rerddapUtils documentation built on Oct. 30, 2026, 1:07 a.m.