#This displays the prices of the 30 stocks in the
#Dow Jones Industrial Average and the Dow Jones Average
#itself.  
def DowJones():
#The thirty stocks currently making up the Dow Jones Industrial Average
  components=[["3M","MMM"],["Alcoa","AA"],["American Express","AXP"],
              ["AT&T","T"],["Bank of America","BAC"],["Boeing","BA"],
              ["Caterpillar","CA"],["Chevron Corporation","CVX"],
              ["Citigroup","C"],["Coca-Cola","KO"],["DuPont","DD"],["ExxonMobil","XOM"],
              ["General Electric","GE"],["General Motors","GM"],["Hewlett-Packard","HPQ"],
              ["Home Depot","HD"],["Intel","INTC"],["IBM","IBM"],["Johnson and Johnson","JNJ"],
              ["JPMorgan Chase","JPM"],["Kraft Foods","KFT"],["McDonald's","MCD"],["Merck","MRK"],
              ["Microsoft","MSFT"],["Pfizer","PFE"],["Procter & Gamble","PG"],
              ["United Technologies Corporation","UTX"],["Verizon Communications","VZ"],
              ["Walmart","WMT"],["Walt Disney","DIS"]]
  dowDivisor=0.125552709
  prices=[0.0]*30
  sum=0.0
  for j in range(0,30):
    result=getStockPrice2(components[j][1])
    prices[j]=float(result[1])
    sum=sum+prices[j]
  print "DOW JONES INDUSTRIAL AVERAGE\n\n\n"
  print "Time: "+result[0]+"\n\n"
  for j in range(0,30):
    print components[j][0],"\t\t\t",prices[j]
  print "\n\n"
  print "Average:\t",round(100*(sum/dowDivisor))/100


from urllib import *
def getStockPrice2(stock_code):
  webstream=urlopen("http://finance.yahoo.com/q?s="+stock_code)
  results=webstream.readlines()
  webstream.close()
#if there's an invalid stock identifier,
#then line 92 of the page contains error information
  if len(results)>92 and results[92].find("There are no") != -1:
    result = 0
#otherwise, line 9 contains the price and time of day,
#which we now proceed to extract from the  string
  else:
    priceline=results[9]
    loc1=priceline.find("yfs_t10")
    loc2=priceline.find(">",loc1)
    loc3=priceline.find("<",loc2)
    loc4=priceline.find("yfs_l10")
    loc5=priceline.find(">",loc4)
    loc6=priceline.find("<",loc5)
    if -1 in [loc1,loc2,loc3,loc4,loc5,loc6]:
#if this happens, then the website's format must
#have changed
      result=-1
    else:
      time=priceline[loc2+1:loc3]
      price=priceline[loc5+1:loc6]
      result=[time,price]
  return result