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Difference between Django's annotate and aggregate methods?
...rage_price': 34.35}
Returns a dictionary containing the average price of all books in the queryset.
Annotation
>>> q = Book.objects.annotate(num_authors=Count('authors'))
>>> q[0].num_authors
2
>>> q[1].num_authors
1
q is the queryset of books, but each book has been...
Accurate way to measure execution times of php scripts
...otime — Return current Unix timestamp with microseconds
If get_as_float is set to TRUE, then microtime() returns a float, which represents the current time in seconds since the Unix epoch accurate to the nearest microsecond.
Example usage:
$start = microtime(true);
while (...) {
}
$...
Correct way to write line to file?
...ing files opened in text mode (the default); use a single '\n' instead, on all platforms.
Some useful reading:
The with statement
open()
'a' is for append, or use
'w' to write with truncation
os (particularly os.linesep)
...
Windows 7, 64 bit, DLL problems
...++ 32-bit executable on my Windows 7 64-bit development box that also has all those Microsoft applications (Visual Studio 2008 + 2010, TFS, SDK, Microsoft Office)...
And it's still running just fine.
...
VS2005中SetUnhandledExceptionFilter函数应用 - C/C++ - 清泛网 - 专注C/C++及内核技术
...在以下三种情况出现。
（1）调用abort函数，并且设置了_CALL_REPORTFAULT选项（这个选项在Release版本是默认设置的）。
（2）启用了运行时安全检查选项，并且在软件运行时检查出安全性错误，例如出现缓存溢出。（安全检查选项 ...
Backbone View: Inherit and extend events from parent
...:
var ChildView = ParentView.extend({
events: function(){
return _.extend({},ParentView.prototype.events,{
'click' : 'onclickChild'
});
}
});
Another would be:
var ParentView = Backbone.View.extend({
originalEvents: {
'click': 'onclick'
},
//Override th...
Get last n lines of a file, similar to tail
... blocks.append(f.read(BLOCK_SIZE))
else:
# file too small, start from begining
f.seek(0,0)
# only read what was not read
blocks.append(f.read(block_end_byte))
lines_found = blocks[-1].count('\n')
lines_to_go -= lines_found
...
How do I concatenate two lists in Python?
...
@Daniel it will create a new list with a shallow copy of the items in the first list, followed by a shallow copy of the items in the second list. Use copy.deepcopy to get deep copies of lists.
– Daniel G
Apr 19 '12 at 14:51
...
Using $_POST to get select option value from HTML
...
Use this way:
$selectOption = $_POST['taskOption'];
But it is always better to give values to your <option> tags.
<select name="taskOption">
<option value="1">First</option>
<option value="2">Second</option>
<...
Chrome hangs after certain amount of data transfered - waiting for available socket
...ins and serve them directly with Nginx for example.
Create a subdomain called img.yoursite.com and load all your images
from there.
Create a subdomain called scripts.yourdomain.com and load all your JS and CSS files from there.
Create a subdomain called sounds.yoursite.com and load all your MP3s...