Me deu este problema aqui quando rodei.
writeOGR(srdf, getwd(), 'POLY', 'ESRI Shapefile')
Error in writeOGR(srdf, getwd(), "POLY", "ESRI Shapefile") :
layer exists, use a new layer name
Onde eu abro arquivos de formato shp e shx?
S
egue CRM final:
#Pacotes
require(shapefiles)
require(rgdal)
require(maptools)
#---------------------------------------------------------------------------
----
#Criação de 4 polígonos
sr1=Polygons(list(Polygon(cbind(c(180114, 180553, 181127, 181477,
181294, 181007, 180409,
180162, 180114), c(332349, 332057, 332342, 333250, 333558, 333676,
332618, 332413, 332349)))),'1')
sr2=Polygons(list(Polygon(cbind(c(180042, 180545, 180553, 180314,
179955, 179142, 179437,
179524, 179979, 180042), c(332373, 332026, 331426, 330889, 330683,
331133, 331623, 332152, 332357, 332373)))),'2')
sr3=Polygons(list(Polygon(cbind(c(179110, 179907, 180433, 180712,
180752, 180329, 179875,
179668, 179572, 179269, 178879, 178600, 178544, 179046, 179110),
c(331086, 330620, 330494, 330265, 330075, 330233, 330336, 330004,
329783, 329665, 329720, 329933, 330478, 331062, 331086)))),'3')
sr4=Polygons(list(Polygon(cbind(c(180304, 180403,179632,179420,180304),
c(332791, 333204, 333635, 333058, 332791)))),'4')
#Converte em polígonos espaciais
sr=SpatialPolygons(list(sr1,sr2,sr3,sr4))
srdf=SpatialPolygonsDataFrame(sr,
data.frame(row.names=c('1','2','3','4'), PIDS=1:4))
#Cria o shapefile
writeOGR(srdf, getwd(), 'POLY', 'ESRI Shapefile')
#Leitura do shapefile
contorno_line_X <- readShapeLines ("POLY.shp")
df.data = as.data.frame(contorno_line_X)
# Seleciono 2 polígono
df.serra15e16 = contorno_line_X[contorno_line_X$PIDS%in%c('1', '4'),]
#Cria o novo shapefile
writeOGR(df.serra15e16, getwd(), 'POLY2s', 'ESRI Shapefile')
#---------------------------------------------------------------------------
----