import string, urllib, re, os, exceptions
JUST_THE_US = 0
class CityNotFound(exceptions.Exception):
pass
def xerox_parc_url(marklist):
avg_lat, avg_lon = max_lat, max_lon = marklist[0]
marks = "%f,%f" % marklist[0]
for lat, lon in marklist[1:]:
marks = marks + ";%f,%f" % (lat, lon)
avg_lat = avg_lat + lat
avg_lon = avg_lon + lon
if lat > max_lat: max_lat = lat
if lon > max_lon: max_lon = lon
avg_lat = avg_lat / len(marklist)
avg_lon = avg_lon / len(marklist)
if len(marklist) == 1:
max_lat, max_lon = avg_lat + 1, avg_lon + 1
diff = max(max_lat - avg_lat, max_lon - avg_lon)
D = {'height': 4 * diff,
'width': 4 * diff,
'lat': avg_lat, 'lon': avg_lon,
'marks': marks}
if JUST_THE_US:
url = ("http://pubweb.parc.xerox.com/map/db=usa/ht=%(height)f" +
"/wd=%(width)f/color=1/mark=%(marks)s/lat=%(lat)f/" +
"lon=%(lon)f/") % D
else:
url = ("http://pubweb.parc.xerox.com/map/color=1/ht=%(height)f" +
"/wd=%(width)f/color=1/mark=%(marks)s/lat=%(lat)f/" +
"lon=%(lon)f/") % D
return url
"""Presumably the intent of the cookbook is largely educational. I should
therefore illuminate something I did really pretty badly in this function.
Notice the ridiculous clumsiness of the "for x in inf.readlines()" loop,
which is utterly and stupidly dependent upon the specific format of the
HTML page returned by the www.astro.ch site. If that format ever changes,
the function breaks. If I had been clever and used htmllib.HTMLParser, I
might have been a bit more immune to modest format changes. If my motivation
persists, I might take a stab at that. No promises."""
def findcity(city, state):
Please_click = re.compile("Please click")
city_re = re.compile(city)
state_re = re.compile(state)
url = ("""http://www.astro.ch/cgi-bin/atlw3/aq.cgi?expr=%s&lang=e"""
% (string.replace(city, " ", "+") + "%2C+" + state))
lst = [ ]
found_please_click = 0
inf = urllib.FancyURLopener().open(url)
for x in inf.readlines():
x = x[:-1]
if Please_click.search(x) != None:
# here is one assumption about unchanging structure
found_please_click = 1
if (city_re.search(x) != None and
state_re.search(x) != None and
found_please_click):
# pick apart the HTML pieces
L = [ ]
for y in string.split(x, '<'):
L = L + string.split(y, '>')
# discard any pieces of zero length
L = filter(lambda x: len(x) > 0, L)
lst.append(L)
inf.close()
try:
# here's another few assumptions
x = lst[0]
lat, lon = x[6], x[10]
except IndexError:
raise CityNotFound
def getdegrees(x, dividers):
def myeval(x):
if len(x) == 2 and x[0] == "0":
return eval(x[1])
return eval(x)
if string.count(x, dividers[0]):
x = map(myeval, string.split(x, dividers[0]))
return x[0] + (x[1] / 60.)
elif string.count(x, dividers[1]):
x = map(myeval, string.split(x, dividers[1]))
return -(x[0] + (x[1] / 60.))
else:
raise "Bogus result", x
return getdegrees(lat, "ns"), getdegrees(lon, "ew")
def showcities(citylist):
marklist = [ ]
for city, state in citylist:
try:
lat, lon = findcity(city, state)
print ("%s, %s:" % (city, state)), lat, lon
marklist.append((lat, lon))
except CityNotFound:
print "%s, %s: not in database?" % (city, state)
url = xerox_parc_url(marklist)
# print url
os.system('netscape "%s"' % url)
citylist = (("Natick", "MA"),
("Rhinebeck", "NY"),
("New Haven", "CT"),
("King of Prussia", "PA"))
citylist1 = (("Mexico City", "Mexico"),
("Acapulco", "Mexico"),
("Abilene", "Texas"),
("Tulum", "Mexico"))
citylist2 = (("Munich", "Germany"),
("London", "England"),
("Madrid", "Spain"),
("Paris", "France"))
showcities(citylist1)
