Draw OS grid squares in OSM format

osmgrid.py

#!/usr/bin/env python
#Draw OS grid squares in OSM format

from ostn02python.OSGB import *
from ostn02python.OSTN02 import *

pointStore = []
vertLines = {}
out = file("grid.osm", "wt")

out.write("<?xml version='1.0' encoding='UTF-8'?>\n")
out.write("<osm version='0.6' upload='true' generator='py'>\n")

for e in range(0, 700000, 100000):
	vertLines[e] = []

	for n in range(0, 1300000, 10000):

		try:
			(x,y,h) = OSGB36_to_ETRS89 (e, n)
		except:
			continue

		#print "OS X (Eastings) "+str(e)
		#print "OS Y (Northings) "+str(n)

		#print "Using the OSGB36_to_ETRS89 conversion gives us the grid position:"
		#print str(x) + "," + str(y) + "," + str(h)

		(gla, glo) = grid_to_ll(x, y)

		#print "The grid position converts to ETRS89 lat,lon (using grid_to_ll) of:"
		#print str((gla, glo))
	
		try:
			ind = pointStore.index((gla, glo))
		except ValueError:
			pointStore.append((gla, glo))
			ind = len(pointStore)-1
			
		vertLines[e].append(ind)

for e in vertLines:
	print e, vertLines[e]

horiLines = {}
for n in range(0, 1300000, 100000):

	horiLines[n] = []
	for e in range(0, 700000, 10000):
	
		try:
			(x,y,h) = OSGB36_to_ETRS89 (e, n)
		except:
			continue

		#print "OS X (Eastings) "+str(e)
		#print "OS Y (Northings) "+str(n)

		#print "Using the OSGB36_to_ETRS89 conversion gives us the grid position:"
		#print str(x) + "," + str(y) + "," + str(h)

		(gla, glo) = grid_to_ll(x, y)

		#print "The grid position converts to ETRS89 lat,lon (using grid_to_ll) of:"
		#print str((gla, glo))
	
		try:
			ind = pointStore.index((gla, glo))
		except ValueError:
			pointStore.append((gla, glo))
			ind = len(pointStore)-1
			
		horiLines[n].append(ind)

for n in horiLines:
	print n, horiLines[n]

for i, pos in enumerate(pointStore):
	out.write("<node id='{0}' action='modify' visible='true' lat='{1}' lon='{2}' />\n".format(-i-1, pos[0], pos[1]))

liCount = 1
for e in vertLines:
	li = vertLines[e]
	out.write("<way id='{0}' action='modify' visible='true'>\n".format(-liCount))
	for pid in li:
	    out.write("<nd ref='{0}' />\n".format(-pid-1))

	out.write("</way>\n")

	liCount += 1 

for n in horiLines:
	li = horiLines[n]
	out.write("<way id='{0}' action='modify' visible='true'>\n".format(-liCount))
	for pid in li:
	    out.write("<nd ref='{0}' />\n".format(-pid-1))

	out.write("</way>\n")

	liCount += 1 


out.write("</osm>\n")