clipLevel1BGeoGeometry: Clip GEDI Full Waveform Geolocations by geometry

In rGEDI: NASA's Global Ecosystem Dynamics Investigation (GEDI) Data Visualization and Processing

Description

This function clips GEDI level1B extracted geolocation (level1BGeo) data within a given geometry

Usage

clipLevel1BGeoGeometry(level1BGeo, polygon_spdf, split_by)

Arguments

level1BGeo	A GEDI Level1b object (output of readLevel1B function). An S4 object of class "data.table".
polygon_spdf	Polygon. An object of class SpatialPolygonsDataFrame-class, which can be loaded as an ESRI shapefile using raster::shapefile() function in the raster package.
split_by	Polygon id. If defined, GEDI data will be clipped by each polygon using the polygon id from table of attribute defined by the user.

Value

Returns an S4 object of class data.table-class containing the clipped GEDI level1B extracted geolocations.

See Also

https://lpdaac.usgs.gov/products/gedi01_bv001/

Examples

# Specifying the path to GEDI level1B data (zip file)
outdir = tempdir()
level1B_fp_zip <- system.file("extdata",
                  "GEDI01_B_2019108080338_O01964_T05337_02_003_01_sub.zip",
                  package="rGEDI")

# Unzipping GEDI level1B data
level1Bpath <- unzip(level1B_fp_zip,exdir = outdir)

# Reading GEDI level1B data (h5 file)
level1b<-readLevel1B(level1Bpath=level1Bpath)

# Extracting GEDI Full Waveform Geolocations
level1bGeo<-getLevel1BGeo(level1b)

# Specifying the path to shapefile
polygon_filepath <- system.file("extdata", "stands_cerrado.shp", package="rGEDI")

# Reading shapefile as SpatialPolygonsDataFrame object
library(raster)
polygon_spdf<-shapefile(polygon_filepath)

# Clipping GEDI Full Waveform Geolocations by Geometry
level1bGeo_clip = clipLevel1BGeoGeometry(level1bGeo, polygon_spdf, split_by="id")

hasLeaflet = require(leaflet)

if (hasLeaflet) {
leaflet() %>%
 addCircleMarkers(level1bGeo_clip$longitude_bin0,
                  level1bGeo_clip$latitude_bin0,
                  radius = 1,
                  opacity = 1,
                  color = "red")  %>%
 addScaleBar(options = list(imperial = FALSE)) %>%
 addPolygons(data=polygon_spdf,weight=1,col = 'white',
             opacity = 1, fillOpacity = 0) %>%
 addProviderTiles(providers$Esri.WorldImagery)
}

close(level1b)

rGEDI documentation built on Jan. 19, 2021, 3:01 p.m.