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MySQL get the date n days ago as a timestamp
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DATE_SUB will do part of it depending on what you want
mysql> SELECT DATE_SUB(NOW(), INTERVAL 30 day);
2009-06-07 21:55:09
mysql> SELECT TIMESTAMP(DATE_SUB(NOW(), INTERVAL 30 day));
2009-06-07 21:55:09
mysql> SELECT U...
Pandas convert dataframe to array of tuples
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How about:
subset = data_set[['data_date', 'data_1', 'data_2']]
tuples = [tuple(x) for x in subset.to_numpy()]
for pandas < 0.24 use
tuples = [tuple(x) for x in subset.values]
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ASP.NET MVC Razor Concatenation
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You should wrap the inner part of the call with ( ):
<li id="item_@(item.TheItemId)">
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Coalesce function for PHP?
...ay element is falsey will result in an error. $input['properties']['range_low'] ?: '?'
– Keyo
Jul 12 '11 at 23:28
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Does C++ support 'finally' blocks? (And what's this 'RAII' I keep hearing about?)
...ing a mutex:
// A class with implements RAII
class lock
{
mutex &m_;
public:
lock(mutex &m)
: m_(m)
{
m.acquire();
}
~lock()
{
m_.release();
}
};
// A class which uses 'mutex' and 'lock' objects
class foo
{
mutex mutex_; // mutex for l...
How do I correctly clone a JavaScript object?
...f a function. Also, an object's prototype is referenced with the attribute __proto__, which is also hidden, and will not be copied by a for/in loop iterating over the source object's attributes. I think __proto__ might be specific to Firefox's JavaScript interpreter and it may be something different...
Representing and solving a maze given an image
...d image directly.
Here is the MATLAB code for BFS:
function path = solve_maze(img_file)
%% Init data
img = imread(img_file);
img = rgb2gray(img);
maze = img > 0;
start = [985 398];
finish = [26 399];
%% Init BFS
n = numel(maze);
Q = zeros(n, 2);
M = zeros([size(maze) 2]);
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What's the proper way to install pip, virtualenv, and distribute for Python?
In my answer to SO question 4314376 , I recommended using ez_setup so that you could then install pip and virtualenv as follows:
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What's the deal with a leading underscore in PHP class methods?
...private with an underscore. In some older classes you'll see /**private*/ __foo() { to give it some extra weight.
I've never heard of developers prefacing all their methods with underscores, so I can't begin to explain what causes that.
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Missing include “bits/c++config.h” when cross compiling 64 bit program on 32 bit in Ubuntu
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While compiling in RHEL 6.2 (x86_64), I installed both 32bit and 64bit libstdc++-dev packages, but I had the "c++config.h no such file or directory" problem.
Resolution:
The directory /usr/include/c++/4.4.6/x86_64-redhat-linux was missing.
I did the foll...