inst/doc/custom_data_sources.R

In geoknife: Web-Processing of Large Gridded Datasets

## ----init, echo=FALSE, include=FALSE------------------------------------------
library(geoknife)
knitr::opts_chunk$set(eval=FALSE)

## ----stencil, echo=T----------------------------------------------------------
#  gconfig(verbose=FALSE)
#  stencil <- webgeom(url="https://www.sciencebase.gov/catalogMaps/mapping/ows/5b68e7e3e4b006a11f75c06a")
#  
#  stencil_geoms <- query(stencil, 'geoms')
#  print(stencil_geoms)

## ----attribute, echo=T--------------------------------------------------------
#  geom(stencil) <- stencil_geoms[2]
#  
#  stencil_attributes <- query(stencil, 'attributes')
#  print(stencil_attributes)

## ----value, echo=T------------------------------------------------------------
#  attribute(stencil) <- stencil_attributes[2]
#  
#  print(query(stencil, 'values'))

## ----fabric, echo=T-----------------------------------------------------------
#  fabric <- webdata(url = 'https://cida.usgs.gov/thredds/dodsC/prism_v2',
#                    variables = c('tmx', 'tmn', 'ppt'),
#                    times = as.POSIXct(c('2000-01-01', '2010-01-01')))
#  print(fabric)

## ----query_fabric, echo=T, warning=F------------------------------------------
#  fabric_variables <- query(fabric, "variables")
#  fabric_times <- query(fabric, "times")
#  
#  print(paste(fabric@url, "has",
#              paste(fabric_variables, collapse = ", "),
#              "variables for the time range", fabric_times[1],
#              "to", fabric_times[2]))

## ----execute, echo=T----------------------------------------------------------
#  prism_yahara_result <- result(geoknife(stencil, fabric, wait = TRUE))

## ----print_execute, echo=F----------------------------------------------------
#  print(paste0("The returned dataframe has ",
#               ncol(prism_yahara_result),
#               " columns with names '",
#               paste(names(prism_yahara_result), collapse = "', '"),
#               "' and ", nrow(prism_yahara_result),
#               " rows from ",
#               prism_yahara_result[1,1],
#               " to ",
#               prism_yahara_result[nrow(prism_yahara_result), 1]))