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When saving, how can you check if a field has changed?
...ally, you want to override the __init__ method of models.Model so that you keep a copy of the original value. This makes it so that you don't have to do another DB lookup (which is always a good thing).
class Person(models.Model):
name = models.CharField()
__original_name = None
def ...
How to format numbers? [duplicate]
...ng() was limited when I first wrote this answer, but the current status looks good.
var n = 100000;
var value = n.toLocaleString(
undefined, // leave undefined to use the browser's locale,
// or use a string like 'en-US' to override it.
{ minimumFractionDigits: 2 }
);
console.lo...
Retrieving a random item from ArrayList [duplicate]
...won't compile anyway since it is unreachable.
Might want to re-write it like:
import java.util.ArrayList;
import java.util.Random;
public class Catalogue
{
private Random randomGenerator;
private ArrayList<Item> catalogue;
public Catalogue()
{
catalogue = new Array...
Maximum filename length in NTFS (Windows XP and Windows Vista)?
...
Adam RosenfieldAdam Rosenfield
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How do I print debug messages in the Google Chrome JavaScript Console?
...Oct 20 '08 at 10:20
Sergey IlinskySergey Ilinsky
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Create numpy matrix filled with NaNs
...alternatives a[:] = numpy.nan here and a.fill(numpy.nan) as posted by Blaenk:
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a.fill(np.nan)"
10000 loops, best of 3: 54.3 usec per loop
$ python -mtimeit "import numpy as np; a = np.empty((100,100));" "a[:] = np.nan"
10000 loops, b...
How to format strings using printf() to get equal length in the output?
I have two functions, one which produces messages like Starting initialization... and another which checks return codes and outputs "Ok" , "Warning" or "Error" . However, the output that is produced is of the different length:
...
Get size of folder or file
...s no built-in way to get the size of a folder, you are going to have to walk the directory tree recursively (using the listFiles() method of a file object that represents a directory) and accumulate the directory size for yourself:
public static long folderSize(File directory) {
long length = 0...
How to initialize an array in Java?
I am initializing an array like this:
10 Answers
10
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How do I get the current username in .NET using C#?
...
juanjuan
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