how to add features like nighttimelights to my polygon shapefile

ifeanyi588 commented 3 years ago

My apologies because I sense this is a trivial question but I am an R programmer but new to GIS analysis. I have a polygon shapefile for Cameroun. I am simply looking to be able to add a variable for night time lights. I know what the indicator in question and from what ImageCollection I'd be getting the data. However, I cant tell which of your tutorials I should be looking at to figure out how to do this. Any quick thoughts would be useful.

csaybar commented 3 years ago

Maybe ?ee_extract can help:

library(rgee)
ee_Initialize()

# World FeatureCollection dataset
countries <- ee$FeatureCollection("USDOS/LSIB_SIMPLE/2017")

# Select Cameroon
cameroon <- countries %>% 
  ee$FeatureCollection$filter(
    ee$Filter$eq('country_na', 'Cameroon')
  ) %>% 
  ee$FeatureCollection$first() %>% 
  ee$Feature() %>% 
  ee$Feature$geometry()

# Display Cameroon map
Map$centerObject(camerun)
Map$addLayer(camerun)

# Get time series
collection <- ee$ImageCollection('NOAA/DMSP-OLS/NIGHTTIME_LIGHTS') %>% 
  ee$ImageCollection$select('stable_lights')

lights_ts <- ee_extract(collection, cameroon)
plot(as.numeric(lights_ts), type ="l")

ifeanyi588 commented 3 years ago

Thanks so much! This is extremely helpful.

r-spatial / rgee

how to add features like nighttimelights to my polygon shapefile #134