Python CSV file parsing into datetime, throwing time format error

Question

I'm using pygtk and glade (python 2.7 32bit interpreter is the most recent it supports) to make an application for a research department, and that requires grabbing a bunch of data from a weather station's csv output and trying to shelve that data in a dictionary for permanent local storage. However, I can't seem to crawl over the wall of storing the date and time information into a datetime object. No matter how many different ways I try to grab the date and time field (represented as a string ex:"11/13/2012 17:43") and put it into a datetime object, I get the same annoying error:

ValueError: time data '' does not match format '%m/%d/%Y %H:%M'

Now for the code in question, it is an event for when a button is clicked on the UI:

def Bupload_clicked(self,widget):
  #Create a file chooser window, with default buttons
  chooser = gtk.FileChooserDialog("Open . .", None, gtk.FILE_CHOOSER_ACTION_OPEN,
     (gtk.STOCK_CANCEL, gtk.RESPONSE_CANCEL, gtk.STOCK_OPEN, gtk.RESPONSE_OK))
  response = chooser.run()

  if response == gtk.RESPONSE_OK: 
     with open(chooser.get_filename(), 'rb') as csvfile:
        reader = csv.reader(csvfile, delimiter='\t', quoting=csv.QUOTE_NONE)
        try:
           for row in reader: #loop through rows of data

              #here is the line of code in question:
              print repr(datetime.datetime(*time.strptime(row[1], "%m/%d/%Y %H:%M") [:5]))

              #rest of code doesn't work until this issue is fixed

        except csv.Error as e:
           sys.exit('file %s, line %d: %s' % (chooser.get_filename(), reader.line_num, e))
  chooser.destroy()

I have tried to accomplish this task in quite a few different ways, using similar questions asked all over the web, including switching the '/' for '-', breaking that one line of code into several lines, etc, but nothing seems to fix the issue.

Also, a side question before you think too hard: The python documentation for strptime() says it looks for [01,12] for %m, [00,24] for %H, [01,31] for %d, etc. But the weather station's CSV file leaves out leading 0's. (ex: "2/1/2013 0:43") would this be causing the errors?

Raw data from CSV file (first 5 lines):

1   11/13/2012 17:43    0   -0.2039 0   43.443  40.2    9.4 0   2.82    70.2    4.375
2   11/13/2012 18:43    0   -0.2039 0   36.651  61.1    0.6 0   0   74.4    4.363
3   11/13/2012 19:43    0   -0.1988 0   32.092  76.1    0.6 0   0.56    74.4    4.357
4   11/13/2012 20:43    0   -0.1988 0   31.591  74.5    0.6 0   1.12    92.7    4.357
5   11/13/2012 21:43    0   -0.1988 0   30.326  82.4    0.6 0   0   223.2   4.351

here is the "in-memory" representation of the list:

#replace the problem line of code with: print row

['1', '11/13/2012 17:43', '0', '-0.2039', '0', '43.443', '40.2', '9.4', '0', '2.82', '70.2', '4.375']
['2', '11/13/2012 18:43', '0', '-0.2039', '0', '36.651', '61.1', '0.6', '0', '0', '74.4', '4.363']
['3', '11/13/2012 19:43', '0', '-0.1988', '0', '32.092', '76.1', '0.6', '0', '0.56', '74.4', '4.357']
['4', '11/13/2012 20:43', '0', '-0.1988', '0', '31.591', '74.5', '0.6', '0', '1.12', '92.7', '4.357']
['5', '11/13/2012 21:43', '0', '-0.1988', '0', '30.326', '82.4', '0.6', '0', '0', '223.2', '4.351']

Answer 1

The problem is not with your format string. The error message

ValueError: time data '' does not match format '%m/%d/%Y %H:%M'

indicates that you are trying to convert the empty string to a time. In other words, for at least one line of your file row[1] == '' and you are effectively calling time.strptime('', '%m/%d/%Y %H:%M').