addVarEEcollection: Add variable from Google Earth Engine Collection

In AfricaBirdData/ABAP: Access to African Bird Atlas Project data from R

Add variable from Google Earth Engine Collection

Description

Add variable from Google Earth Engine Collection

Usage

addVarEEcollection(
  ee_pentads,
  collection,
  dates,
  temp_reducer,
  spt_reducer,
  bands = NULL,
  unmask = FALSE
)

Arguments

ee_pentads	A feature collection with the pentads we want to annotate. We need to upload an sf object with the pentads to GEE.
collection	Either a character string with the name of the collection we want to use or a GEE collection produced with ee$ImageCollection(). See GEE catalog.
dates	A character vector with two elements c(start, end). Format must be "yyyy-mm-dd".
temp_reducer	A character string specifying the function to summarize collection across time. It is common to use "mean", "sum" or "count", but there are many others, see 'ee.Reducer' under Client Libraries at https://developers.google.com/earth-engine/apidocs.
spt_reducer	A character string specifying the function apply when extracting values for each pentad. It is common to use "mean", "sum" or "count", but there are many others, see 'ee.Reducer' under Client Libraries at https://developers.google.com/earth-engine/apidocs.
bands	Select specific bands from the image. If not specified, pentads will be annotated with all bands (one column for each band).
unmask	GEE masks missing values, which means they are not used for computing means, counts, etc. Sometimes we might want to avoid this behaviour and use 0 instead of NA. If so, set unmask to TRUE.

Value

A dataframe similar to ee_pentads with variables added from the bands selected from collection. Note that following rgee the name of the new variables will be the selected band (bands or else all bands from collection followed by the spatial reducer spt_reducer. The temporal reducer temp_reducer does not appear in the name, and therefore, it is up to the user to keep track of how the temporal reducer summarized the collection.

Examples

## Not run: 
# Load the remote data asset
ee_data <- ee$FeatureCollection(assetId)  # assetId must correspond to an asset in your GEE account

# Annotate with TerraClimate dataset
pentads_tmmn <- addVarEEcollection(ee_pentads = ee_data,
                                   collection = "IDAHO_EPSCOR/TERRACLIMATE",
                                   dates = c("2010-01-01", "2011-01-01"),
                                   temp_reducer = "mean",
                                   spt_reducer = "mean",
                                   bands = "tmmn")

## End(Not run)

AfricaBirdData/ABAP documentation built on Aug. 4, 2024, 4:41 p.m.