Closed Leprechault closed 2 years ago
i hope it helps
Thanks @csaybar, now it works!!!
- download parameters (Google Drive)
Table ID : rgee_file_70c1bbd7e46
Google user : ndef
Folder name : rgee_backup
Date : 2022_10_08_09_37_33
Polling for task <id: NO52LT3A3RRAAGRRLDLLCVYE, time: 0s>.
Polling for task <id: NO52LT3A3RRAAGRRLDLLCVYE, time: 5s>.
Polling for task <id: NO52LT3A3RRAAGRRLDLLCVYE, time: 10s>.
State: COMPLETED
> ee_mean
S1B_IW_GRDH_1SDV_20191210T084832_20191210T084857_019300_024710_A03C_constant
1 2.426008
S1B_IW_GRDH_1SDV_20191222T084832_20191222T084857_019475_024CA1_193D_constant
1 2.434232
I do:
library(tidyverse)
library(rgee)
library(sf)
ee_Initialize(drive=TRUE)
# Define a Region of interest
roi <-ee$Geometry$Point(-52.19032,-30.25413)$buffer(500)
# Sentinel-1 dataset into the Earth Engine’s public data archive ------------
s1 <- ee$ImageCollection("COPERNICUS/S1_GRD")$filter(ee$Filter$listContains("transmitterReceiverPolarisation", "VV"))$filter(ee$Filter$listContains("transmitterReceiverPolarisation","VH"))$filter(ee$Filter$eq("instrumentMode", "IW"))
# Radar vegetation index - RVI
RVI = function(img){
img_band_selected <- img$expression(
expression = '4*vh/(vv+vh)',
opt_map = list(
'vv' = img$select('VV'),
'vh' = img$select('VH')
)
)
return(img_band_selected)
}
s1_roi <- s1$filterBounds(roi)$filter(ee$Filter$date(as.character("2019-12-04"), as.character("2020-01-03")))$map(RVI)
#Extract average radar vegetation index (RVI) values
ee_mean<- ee_extract(
x = s1_roi,
y = roi,
scale = 10,
fun = ee$Reducer$mean(),
via = "drive"
)
ee_mean
I'd like to create a temporal mean for the Radar vegetation index - RVI in a target
roi
. In my example:But the output is not OK and almost doesn't have examples with vegetation index for Sentinel-1 band C.
Please any help with it?