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Why does ++[[]][+[]]+[+[]] return the string “10”?
...array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by one and return the incremented result”. So ++[[]][0] is equivalent to Number(A) + 1 (or +A + 1).
Again, we can simplify the me...
Get the full URL in PHP
...
Have a look at $_SERVER['REQUEST_URI'], i.e.
$actual_link = "http://$_SERVER[HTTP_HOST]$_SERVER[REQUEST_URI]";
(Note that the double quoted string syntax is perfectly correct)
If you want to support both HTTP and HTTPS, you can use
$act...
What kind of leaks does automatic reference counting in Objective-C not prevent or minimize?
... platforms, memory leaks are often caused by unreleased pointers. Traditionally, it has always been of utmost importance to check your allocs, copies and retains to make sure each has a corresponding release message.
...
Pandas percentage of total with groupby
... is a table of some kind, so 100 * x doesn't intuitively make sense (especially when some of the cells contain strings like AZ, ...).
– dhardy
Feb 6 '15 at 9:42
6
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Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
How do I export UIImage array as a movie?
...riter has an input of type AVAssetWriterInput, which in turn has a method called appendSampleBuffer: that lets you add individual frames to a video stream. Essentially you’ll have to:
1) Wire the writer:
NSError *error = nil;
AVAssetWriter *videoWriter = [[AVAssetWriter alloc] initWithURL:
[...
Delete multiple objects in django
...sing a webpage. There is no category to select from so I can't delete from all of them like that. Do I have to implement my own delete form and process it in django or does django have a way to already do this? As its implemented in the admin interface.
...
Role/Purpose of ContextLoaderListener in Spring?
...ates the WebApplicationContext. Otherwise it would need to be created manually.
– sourcedelica
Jul 26 '13 at 15:21
do...
What does the “at” (@) symbol do in Python?
...
Example
class Pizza(object):
def __init__(self):
self.toppings = []
def __call__(self, topping):
# When using '@instance_of_pizza' before a function definition
# the function gets passed onto 'topping'.
self.toppings.appe...
How do I activate a virtualenv inside PyCharm's terminal?
...with multiple projects, each which might have a different virtualenv, I'd call the ".pycharmrc" file something different, and perhaps put it into the env directory itself. ~/pycharmenv/bin/terminalactivate sounds like a good option.
– Chris Cogdon
Mar 10 '14 at...