obpg_query: A basic query function to retrieve one or more datasets
In BigelowLab/obpgcrawler: obpgcrawler

Description Usage Arguments Value See Also Examples

A basic query function to retrieve one or more datasets

  obpg_query(top = "https://oceandata.sci.gsfc.nasa.gov/opendap/catalog.xml",
  platform = "MODISA", product = "L3SMI",
  year = format(as.Date(Sys.Date()), "%Y"),
  day = format(as.Date(Sys.Date()), "%j"), what = c("all",
  "most_recent", "within", "before", "after")[1], date_filter = NULL,
  greplargs = NULL, verbose = FALSE, userpassword = c(user = "user",
  password = "password"))

`top`	character, uri of the top catalog
`platform`	character, the name of the platform (MODISA, MODIST, OCTS, SeaWiFS, VIIRS, etc.)
`product`	character, the product type (L3SMI, etc.)
`year`	character or numeric, four digit year(s) - ignored if what is not 'all'
`day`	character or numeric, three digit year of day(s) - ignored if what is not 'all'. You can improve efficiency by preselecting days for months, days, or seasons.
`what`	character, optional filters all - return all occurences, the default, used with year and day, date_filter = NULL most_recent - return only the most recent, date_filter = NULL within - return the occurrences bounded by date_filter first and secomd elements before - return the occurences prior to the first date_filter element after - return the occurrences after the first date_filter element
`date_filter`	POSIXct or Date, one or two element vector populated according to the `what` parameter. By default NULL. It is an error to not match the value of date_filter
`greplargs`	list or NULL, if a list the provide two elements, pattern=character and fixed=logical, which are arguments for `grepl` If fixed is FALSE then be sure to provide a regex for the pattern value.
`verbose`	logical, by default FALSE
`userpassword`	character, a two element named vector with elements "user" and "password"

list of DatasetRefClass or NULL

get_monthdays, get_8days and get_seasondays

   ## Not run: 
      query <- obpg_query(
         top = 'http://oceandata.sci.gsfc.nasa.gov/opendap/catalog.xml',
         platform = 'MODISA',
         product = 'L3SMI',
         what = 'most_recent',
         greplargs = list(pattern='8D_CHL_chlor_a_4km', fixed = TRUE))
      query <- obpg_query(
         top = 'http://oceandata.sci.gsfc.nasa.gov/opendap/catalog.xml',
         platform = 'MODISA',
         product = 'L3SMI',
         what = 'within',
         date_filter = as.POSIXct(c("2008-01-01", "2008-06-01"), format = "%Y-%m-%d"),
         greplargs = list(
            chl = list(pattern='8D_CHL_chlor_a_4km', fixed = TRUE),
            sst = list(pattern='8D_SST_sst_4km', fixed = TRUE)) )
   
## End(Not run)