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Best way to test for a variable's existence in PHP; isset() is clearly broken
... This looks a bit ugly to me, but in the case where you're actually checking an array element, it makes much more sense: isset($foo[$bar]) becomes array_key_exists($bar, $foo)
– Arild
Aug 25 '14 at 14:12
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How to split a string and assign it to variables
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I like Go but I wouldn't call this flexible :D
– Pijusn
May 25 '17 at 4:27
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how do you filter pandas dataframes by multiple columns
...r function using query in pandas. Here you have filtering of df results by all the kwargs parameters. Dont' forgot to add some validators(kwargs filtering) to get filter function for your own df.
def filter(df, **kwargs):
query_list = []
for key in kwargs.keys():
query_list.append(f...
How to get the request parameters in Symfony 2?
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The naming is not all that intuitive:
use Symfony\Component\HttpFoundation\Request;
public function updateAction(Request $request)
{
// $_GET parameters
$request->query->get('name');
// $_POST parameters
$request->r...
Git: fatal: Pathspec is in submodule
I'm trying to get TravisCI to automatically deploy my Hakyll static site, according to this guide .
5 Answers
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Oracle TNS names not showing when adding new connection to SQL Developer
...cognized, use the following procedure:
Define an environmental variable called TNS_ADMIN to point to the folder that contains your tnsnames.ora file.
In Windows, this is done by navigating to Control Panel > System > Advanced system settings > Environment Variables...
In Linux, define...
error LNK2019: 无法解析的外部符号_socket，该符号在函数 中被引用 - c++1...
1>NetClient.obj : error LNK2019: 无法解析的外部符号 _closesocket@4，该符号在函数 _main 中被引用
1>NetClient.obj : error LNK2019: 无法解析的外部符号 _inet_ntoa@4，该符号在函数 _main 中被引用
1>NetClient.obj : error LNK2019: 无法解析的外部符...
How can I apply a function to every row/column of a matrix in MATLAB?
...umns if there's only one row, or higher dimensions if the lower dimensions all have size==1). However, bsxfun works for any function, including (and especially) user-defined functions.
For example, let's say you have a matrix A and a row vector B. E.g., let's say:
A = [1 2 3;
4 5 6;
7 8 ...
Understanding generators in Python
...A generator is simply a function which returns an object on which you can call next, such that for every call it returns some value, until it raises a StopIteration exception, signaling that all values have been generated. Such an object is called an iterator.
Normal functions return a single value...
How to get position of a certain element in strings vector, to use it as an index in ints vector?
...e use size_t we must be careful not to subtract a larger iterator from a smaller iterator.
– dasblinkenlight
Oct 17 '17 at 10:49
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