Digimap featurecodes and numbers of coordinates in each
| Feature | Codes | Coordinates |
|---|---|---|
| Map data were downloaded in DXF format and hazard lists were extracted using specially written PASCAL programs. Coordinates are specified to one metre precision but OS warns that this is not a meaningful statement of ground accuracy. OS quoted tolerances on their 1:250 000 printed maps, derived from these data, suggest maximum ground errors of 25 metres for points and vertices (0.1 mm on map) and 50 metres for interpolations (0.2 mm). Mean errors are probably around 20 metres. | ||
| Bus/coach stations | (direct map reading) | 455 |
| OS bus stations | (direct map reading) | 302 |
| Railway stations | 5520 | 2531 |
| Railways | 5510,5511,5512,5513 | 78378 |
| Motorways | 5310,5312 | 9984 |
| A class roads | 5330,5332,5333,5335 | 146943 |
| B class roads | 5340,5342,5343,5345 | 164227 |
| Minor roads >4 m wide | 5350 | 382817 |
| Minor roads <4 m wide | 5405 | 481880 |
| River, main, lower | 5213 | 15505 |
| Other rivers | 5211,5212,5221,5222,5230 | 857107 |