-1 returns second to last item in python list -

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i using python 3.4 write script pull data yahoo finance's chartapi page using urllib pull data , store in text file , numpy unpack it. however, when ever try access last element in list using [-1] end second last element instead of last element.

here relevant code:

import urllib.request import numpy np  def n_year_data(symbol):     tempfile = 'temp.txt'     open(tempfile,'w+') # clear previous content      yahoochartapi = 'http://chartapi.finance.yahoo.com/instrument/1.0/'+symbol+'/chartdata;type=quote;range=1y/csv'     urllib.request.urlopen(yahoochartapi) f:         sourcecode = f.read().decode('utf-8')     splitsource = sourcecode.split('\n')      eachline in splitsource:         splitline = eachline.split(',')          if len(splitline) == 6:              if 'values' not in eachline:                 savefile = open(tempfile,'a')                 linetowrite = eachline+'\n'                 savefile.write(linetowrite)      date, close, high, low, openprice, volume = np.loadtxt(tempfile, delimiter=',', unpack=true)      print(date[-1])  n_year_data("goog")

the code above should return last date, 20150707. returns 20150706 date before last date. furthermore when @ text file, dates there , should be. in advance help, or advice.

since you not correctly closing file after finish writing, might end having problem, or other potential problems.

don't open , append file in loop.

consider using this, instead:

with open('temp.txt', 'w') f:    item in iterable:        f.write('hello')  open('temp.txt', 'r') f:    line in f:        print(line)

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