I'm learning about use R to image processing. In this way, I'm trying to generate a polygon, which I will use top segment objects in a image. I've be trying some strategies and, in my searches, I found this post (SpatialPolygons - Creating a set of polygons in R from coordinates) which uses a similar strategy. trying to reproduce the results, with my data, I found a error. These are my steps. Take the coordinates, for example:
[,1] [,2]
[1,] 221 262
[2,] 226 260
[3,] 222 261
[4,] 221 262
[5,] 220 262
[6,] 219 262
[7,] 218 263
[8,] 218 264
[9,] 218 265
[10,] 218 266
[11,] 217 266
[12,] 217 267
[13,] 216 268
[14,] 216 269
[15,] 215 269
[16,] 215 270
[17,] 215 271
[18,] 216 272
[19,] 216 274
[20,] 216 275
[21,] 216 276
[22,] 216 277
[23,] 216 278
[24,] 217 279
[25,] 218 279
[26,] 219 279
[27,] 223 279
[28,] 224 279
[29,] 225 279
[30,] 226 279
[31,] 227 279
[32,] 228 279
[33,] 228 278
[34,] 231 278
[35,] 231 277
[36,] 232 277
[37,] 233 277
[38,] 233 276
[39,] 234 276
[40,] 235 276
[41,] 235 275
[42,] 236 275
[43,] 237 275
[44,] 237 274
[45,] 237 273
[46,] 238 273
[47,] 238 272
[48,] 239 272
[49,] 239 271
[50,] 239 270
[51,] 239 267
[52,] 239 266
[53,] 239 265
[54,] 240 265
[55,] 241 265
[56,] 241 264
[57,] 241 263
[58,] 241 262
[59,] 241 261
[60,] 241 260
[61,] 241 259
[62,] 241 258
[63,] 240 257
[64,] 239 257
[65,] 238 257
[66,] 237 257
[67,] 236 257
[68,] 235 257
[69,] 234 257
[70,] 233 257
[71,] 232 257
[72,] 231 258
[73,] 230 258
[74,] 229 258
[75,] 228 258
[76,] 227 258
[77,] 226 258
[78,] 226 259
[79,] 225 260
[80,] 224 261
[81,] 223 262
[82,] 221 262
I put these coordinates in a variable, p, and did:
ps <- SpatialPolygons(list(Polygons(list(Polygon(p)),1)))
And the error returned was:
Error in validObject(res) :
invalid class “SpatialPolygons” object: superclass "SpatialPolygonsNULL" not defined in the environment of the object's class
Anyone have any clue to solve this??
Thanks in advance