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Convert SVG image to PNG with PHP
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That's funny you asked this, I just did this recently for my work's site and I was thinking I should write a tutorial... Here is how to do it with PHP/Imagick, which uses ImageMagick:
$usmap = '/path/to/blank/us-map.svg';
$im = new Imagick();
$svg = file_get_contents($usmap);
/*loop to color eac...
SQL JOIN - WHERE clause vs. ON clause
... JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will return an order and its lines, if any, for order number 12345. The second will return all orders, but...
Setting multiple attributes for an element at once with JavaScript
...ibute change. Accessing this.getAttribute('your-attr') for both attributes and exiting if one of them is still empty is a first solution BUT it does not handle the case where only one attribute is set, and the other one already has a previous value. But god helps this is not the question actually ob...
Why can't I forward-declare a class in a namespace using double colons?
...viously declared) entities. They can't be used to introduce new entities.
And you are in fact "reopening" the namespace to declare new entities. If the class Class is later defined as a member of different namespace - it is a completely different class that has nothing to do with the one you declar...
How to clear gradle cache?
I'm trying to use Android Studio, and the first time I boot it up, it takes like 45 MINUTES to compile... If I don't quit the application, it is okay - each subsequent compilation/running the app will take around 45 seconds.
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Is std::vector copying the objects with a push_back?
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Yes, std::vector<T>::push_back() creates a copy of the argument and stores it in the vector. If you want to store pointers to objects in your vector, create a std::vector<whatever*> instead of std::vector<whatever>.
However, you need to make sure that the objects referenced...
Find object by id in an array of JavaScript objects
... '45').map(x => x.foo);
Side note: methods like find() or filter(), and arrow functions are not supported by older browsers (like IE), so if you want to support these browsers, you should transpile your code using Babel (with the polyfill).
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Count the items from a IEnumerable without iterating?
Let's say I want iterate on those and write something like processing #n of #m.
19 Answers
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How to see which flags -march=native will activate?
...get doesn't display CPU cache information, of which the methods both elias and 42n4 below have listed. Specifically, on gcc 4.9.2 on a Phenom, the output includes these: --param l1-cache-size=64 --param l1-cache-line-size=64 --param l2-cache-size=512
– Daniel Santos
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What does if __name__ == “__main__”: do?
... file, it does two things:
it sets a few special variables like __name__, and then
it executes all of the code found in the file.
Let's see how this works and how it relates to your question about the __name__ checks we always see in Python scripts.
Code Sample
Let's use a slightly different cod...