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# snippets R raster
library(raster)
# creer raster vide type entier 60 x 80 km, res 500 m
rvide.crs <- CRS("+init=EPSG:2154")
rvide.ext <- extent(c(688500,748500,6292500,6372500))
rvide.val <- rep(0, 120*160)
rvide <- raster(crs=rvide.crs, ext=rvide.ext, resolution=500, vals=rvide.val)
writeRaster(rvide, filename="D:/GIS_DATA/HomeRange/RSpatial/reference_grid2.asc", format="ascii", datatype='INT2S', NAflag=-9999)
CREATE TABLE carto.parcelles
(
num_fiche serial NOT NULL,
date_debut date,
date_fin date,
surface numeric(10, 2),
personnes text,
code_dept character(10),
laboratoire text,
@cybernar
cybernar / ncdf_extract_values.R
Last active November 23, 2016 12:10
Extract values at XY position from NetCDF file
library(raster)
library(ncdf4)
library(maptools)
# netcdf file from ftp://aspen.atmos.albany.edu/pdsi/cmip5/scPDSIpm/pdsisc.monthly.maps.1900-2099.r2.5x2.5.EnsAvg14Models.TP2.ipe=2.nc
# shp file from http://www.naturalearthdata.com/http//www.naturalearthdata.com/download/50m/cultural/ne_50m_airports.zip
# load netcdf file as a raster brick
f <- "D:/bacasable/pdsisc.monthly.maps.1900-2099.r2.5x2.5.EnsAvg14Models.TP2.ipe=2.nc"
rbr <- brick(f, varname="pdsisc")
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@cybernar
cybernar / S2_reflectance.R
Created January 21, 2019 18:29
Process Sentinel2 reflectance data from Theia
## CALCUL NDVI avec masque nuages
## Image couleur naturel Sentinel2
library(raster)
library(rgdal)
library(stringr)
# random walk
f_point_in_circle <- function(x_from, y_from, step_dist=10, step_number=100) {
angle <- runif(step_number, 0, 360)
x_diff <- step_dist * cos(angle)
y_diff <- step_dist * sin(angle)
x_pos <- x_from + cumsum(x_diff)
y_pos <- y_from + cumsum(y_diff)
cbind(x=x_pos, y=y_pos)
}
@cybernar
cybernar / display_ff_bookmarks.html
Last active February 8, 2019 18:09
Display Firefox bookmarks (after exporting them to json)
<!DOCTYPE html>
<html lang="fr">
<head>
<meta charset="utf-8" />
<!--
<link rel="stylesheet" href="design.css" />
<script src="script.js"></script>
-->
<script src="bookmarks-2019-02-08.js"></script>
<link rel="stylesheet" type="text/css" href="https://fonts.googleapis.com/css?family=Roboto">
@cybernar
cybernar / safran2raster.R
Created May 3, 2019 13:28
Create raster from SAFRAN csv file
# safran 2 raster
library(data.table)
library(raster)
library(sf)
# ##### FONCTIONS #####
# genere 1 raster à partir de DT(data.table) pour la variable et la date spécifiées
@cybernar
cybernar / sf_snippets.R
Last active April 10, 2020 17:01
sf snippets
# genere sf à partir de data.frame
df2sf <- function(df, x_col, y_col, epsg) {
geomdef <- paste0("POINT(", df[[x_col]], " ", df[[y_col]],")")
sfc <- st_as_sfc(geomdef, epsg)
st_geometry(df) <- sfc
df
}
# autre solution
sf_points <- st_as_sf(df, crs=4326, coords=c("longitude", "latitude"), remove=FALSE)