I need to read a large file, line by line. Lets say that file has more than 5GB and I need to read each line, but obviously I do not want to use readlines() because it will create a very large list in the memory. How will the code below work for this case? Is … Read more
I’m using Python 2 to parse JSON from ASCII encoded text files. When loading these files with either json or simplejson, all my string values are cast to Unicode objects instead of string objects. The problem is, I have to use the data with some libraries that only accept string objects. I can’t change the … Read more
I found this script online: import httplib, urllib params = urllib.urlencode({‘number’: 12524, ‘type’: ‘issue’, ‘action’: ‘show’}) headers = {“Content-type”: “application/x-www-form-urlencoded”, “Accept”: “text/plain”} conn = httplib.HTTPConnection(“bugs.python.org”) conn.request(“POST”, “”, params, headers) response = conn.getresponse() print response.status, response.reason 302 Found data = response.read() data ‘Redirecting to <a href=”http://bugs.python.org/issue12524″>http://bugs.python.org/issue12524</a>’ conn.close() But I don’t understand how to use it with … Read more
When piping the output of a Python program, the Python interpreter gets confused about encoding and sets it to None. This means a program like this: # -*- coding: utf-8 -*- print u”åäö” will work fine when run normally, but fail with: UnicodeEncodeError: ‘ascii’ codec can’t encode character u’\xa0′ in position 0: ordinal not in … Read more
I’m curious, whether there is any way to print formatted numpy.arrays, e.g., in a way similar to this: x = 1.23456 print ‘%.3f’ % x If I want to print the numpy.array of floats, it prints several decimals, often in ‘scientific’ format, which is rather hard to read even for low-dimensional arrays. However, numpy.array apparently … Read more
I am using Python version 2.5.4 and install MySQL version 5.0 and Django. Django is working fine with Python, but not MySQL. I am using it in Windows Vista. 3Best Answer 31
I have a Unicode string in Python, and I would like to remove all the accents (diacritics). I found on the web an elegant way to do this (in Java): convert the Unicode string to its long normalized form (with a separate character for letters and diacritics) remove all the characters whose Unicode type is … Read more
Are there any applicable differences between dict.items() and dict.iteritems()? From the Python docs: dict.items(): Return a copy of the dictionary’s list of (key, value) pairs. dict.iteritems(): Return an iterator over the dictionary’s (key, value) pairs. If I run the code below, each seems to return a reference to the same object. Are there any subtle … Read more
I have two integer values a and b, but I need their ratio in floating point. I know that a < b and I want to calculate a / b, so if I use integer division I’ll always get 0 with a remainder of a. How can I force c to be a floating point … Read more
While asking this question, I realized I didn’t know much about raw strings. For somebody claiming to be a Django trainer, this sucks. I know what an encoding is, and I know what u” alone does since I get what is Unicode. But what does r” do exactly? What kind of string does it result … Read more
