Does some wonky parsing to get latest btc,ltc,usd info from btc-e.com and sees if there are discrepancies in the mutual ratios.

btc-arb.py

import httplib
import urllib
import json

pairs= {
'btc_usd' : "1",
'ltc_btc' : "10",
'ltc_usd' : "14"
}


def latest(pair):
  params = {"act": "orders_update", "pair":pair} 
  params = urllib.urlencode(params)
  headers = {"Content-type": "application/x-www-form-urlencoded"}
  conn = httplib.HTTPSConnection("btc-e.com")
  conn.request("POST", "/ajax/order.php", params, headers)

  response = conn.getresponse()
   
  #print response
  #print response.status, response.reason
  val = json.load(response)
  print pairs.keys()[pairs.values().index(pair)], "is", val['last'][pair]
  return val['last'][pair]



btc_usd = latest(pairs['btc_usd'])
ltc_btc = latest(pairs['ltc_btc'])
ltc_usd = latest(pairs['ltc_usd'])

dollars = 1000
#1000 dollars in litecoin
num_ltc = dollars / float(ltc_usd)
print dollars, "dollars =", num_ltc, "litecoins"

#1000 dollars in bitcoin
num_btc = 1000 / float(btc_usd)
print dollars, "dollars =", num_btc, "bitcoins"

#In theory num_btc / ltc_btc should ruougly equal num_ltc
ideal_ltc = num_btc / ltc_btc
print "If we bought", dollars, "worth of bitcoin and then traded it for litecoin we would have", ideal_ltc
print "we actually have", num_ltc


profit = ideal_ltc - num_ltc
profitD = profit * ltc_usd
if(profit > 0):
  print "that allows us to make a profit of", profit, "litecoins by going btc->ltc vs usd->ltc"
  print "that is ", profitD, "dollars"
elif(profit < 0):
  print "that allows us to make a profit of", profit * -1, "litecoins by going usd->ltc vs btc->ltc "
  print "that is ", profitD * -1, "dollars"

Thanks for this code. It currently complains that "No JSON object could be decoded" when I try to execute the code. Has this been blocked now?

Cheers
W