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Check if OneToOneField is None in Django
...ately, this doesn't work all the time. In case you want to work with select_related() now or in the future -- or maybe even to be sure you also handle other sorts of magic which may happen elsewhere -- you have to extend the test as follows: if hasattr(object, 'onetoonerevrelattr') and object.onetoo...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...
urlencode vs rawurlencode?
...php)
Returns a string in which all non-alphanumeric characters except -_.~ have been replaced with a percent (%) sign followed by two hex digits. This is the encoding described in » RFC 3986 for protecting literal characters from being interpreted as special URL delimiters, and for protecting U...
What's the _ underscore representative of in Swift References?
...
Both answers were correct but I want to clarify a little bit more.
_ is used to modify external parameter name behavior for methods.
In Local and External Parameter Names for Methods section of the documentation, it says:
Swift gives the first parameter name in a method a local paramete...
How do I use prepared statements in SQlite in Android?
... Below are some examples:
Create a table
String sql = "CREATE TABLE table_name (column_1 INTEGER PRIMARY KEY, column_2 TEXT)";
SQLiteStatement stmt = db.compileStatement(sql);
stmt.execute();
The execute() method does not return a value so it is appropriate to use with CREATE and DROP but not in...
How to crop an image in OpenCV using Python
...y simple. Use numpy slicing.
import cv2
img = cv2.imread("lenna.png")
crop_img = img[y:y+h, x:x+w]
cv2.imshow("cropped", crop_img)
cv2.waitKey(0)
share
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improve this answer
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Python: Why is functools.partial necessary?
...mbda:
>>> pickle.dumps(partial(int))
'cfunctools\npartial\np0\n(c__builtin__\nint\np1\ntp2\nRp3\n(g1\n(tNNtp4\nb.'
>>> pickle.dumps(lambda x: int(x))
Traceback (most recent call last):
File "<ipython-input-11-e32d5a050739>", line 1, in <module>
pickle.dumps(lambd...
Android - Camera preview is sideways
...Parameters();
Display display = ((WindowManager)getSystemService(WINDOW_SERVICE)).getDefaultDisplay();
if(display.getRotation() == Surface.ROTATION_0) {
parameters.setPreviewSize(height, width);
mCamera.setDisplayOrientation(90);
}
if(disp...
How to [recursively] Zip a directory in PHP?
...ion to be loaded.
function Zip($source, $destination)
{
if (!extension_loaded('zip') || !file_exists($source)) {
return false;
}
$zip = new ZipArchive();
if (!$zip->open($destination, ZIPARCHIVE::CREATE)) {
return false;
}
$source = str_replace('\\', '/'...
What is the difference between ManualResetEvent and AutoResetEvent in .NET?
...ass ManualResetEventSample
{
private readonly ManualResetEvent _manualReset = new ManualResetEvent(false);
public void RunAll()
{
new Thread(Worker1).Start();
new Thread(Worker2).Start();
new Thread(Worker3).Start();
Consol...