clipLevel1BGeoGeometry: Clip GEDI Full Waveform Geolocations by geometry

In carlos-alberto-silva/rGEDI: NASA's Global Ecosystem Dynamics Investigation (GEDI) Data Visualization and Processing

Clip GEDI Full Waveform Geolocations by geometry

Description

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

Usage

clipLevel1BGeoGeometry(level1BGeo, polygon, split_by = "id")

Arguments

level1BGeo	A data.table::data.table resulting from getLevel1BGeo() function.
polygon	Polygon. An object of class sf::sf, which can be loaded as an ESRI shapefile using sf::st_read function in the sf 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::data.table containing the clipped GEDI level1B extracted geolocations.

See Also

https://lpdaac.usgs.gov/products/gedi01_bv002/

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 sf object
library(sf)
polygon <- sf::st_read(polygon_filepath)

# Clipping GEDI Full Waveform Geolocations by Geometry
level1BGeo_clip <- clipLevel1BGeoGeometry(level1BGeo, polygon, 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, weight = 1, col = "white",
      opacity = 1, fillOpacity = 0
    ) %>%
    addProviderTiles(providers$Esri.WorldImagery)
}

close(level1b)

carlos-alberto-silva/rGEDI documentation built on Oct. 18, 2024, 4:46 a.m.