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Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
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NOTE: PyPy is more mature and better supported now than it was in 2013, when this question was asked. Avoid drawing conclusions from out-of-date information.
PyPy, as others have been quick to mention, has tenuous support for C extensions. It has support, but typical...
Dynamically creating keys in a JavaScript associative array
...l = dict["2bob2"];
// Read value of our cool secret key
val = dict[key];
Now let's change values:
// Change the value of fred
dict.fred = "astra";
// The assignment creates and/or replaces key-value pairs
// Change the value of 2bob2
dict["2bob2"] = [1, 2, 3]; // Any legal value can be used
// ...
What is __init__.py for?
...make two blank files, the init.py file (with underscores) and datetime.py. Now open an interpreter, import sys, and issue sys.path.insert(0, '/path/to/datetime'), replacing that path with the path to whatever directory you just made. Now try something like from datetime import datetime;datetime.now(...
Using “Object.create” instead of “new”
...bject.create has any advantages over using new. On the contrary there are known problems with it. Sam Elsamman describes what happens when there are nested objects and Object.create(...) is used:
var Animal = {
traits: {},
}
var lion = Object.create(Animal);
lion.traits.legs = 4;
var bird = Obj...
How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
...ally inherit A. D's object size is increased because it stores 2 pointers now; however there is only one A now.
So B::A and C::A are the same and so there can be no ambiguous calls from D. If you don't use virtual inheritance you have the second diagram above. And any call to a member of A the...
How to move Jenkins from one PC to another
...evelopment PC. I installed it on my development PC, because I had limited knowledge on this tool; so I tested on it in my development PC. Now, I feel comfortable with Jenkins as my long term "partner" in the build process and would like to "move" this Jenkins to a dedicated server.
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Common elements in two lists
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Use Collection#retainAll().
listA.retainAll(listB);
// listA now contains only the elements which are also contained in listB.
If you want to avoid that changes are being affected in listA, then you need to create a new one.
List<Integer> common = new ArrayList<Integer>(...
Building a complete online payment gateway like Paypal [closed]
...een there and done that. It was a lot easier about 10 years ago than it is now, but if you have a phenomenal amount of time, money and patience available, it is still possible.
You will need to contact an acquiring bank. You didnt say what region of the world you are in, but by this I dont mean a ...
Bash: infinite sleep (infinite blocking)
...initrc . In my .xinitrc I start my window manager using /usr/bin/mywm . Now, if I kill my WM (in order to f.e. test some other WM), X will terminate too because the .xinitrc script reached EOF.
So I added this at the end of my .xinitrc :
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Confusion between factor levels and factor labels
...seems to be a difference between levels and labels of a factor in R.
Up to now, I always thought that levels were the 'real' name of factor levels, and labels were the names used for output (such as tables and plots). Obviously, this is not the case, as the following example shows:
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