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unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
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What makes JNI calls slow?
...thods, in 2010 I measured calls at an average 40 ns on my Windows desktop, and 11 ns on my Mac desktop. Unless you're making many calls, you're not going to notice.
That said, calling a native method can be slower than making a normal Java method call. Causes include:
Native methods will not be i...
How do I implement an Objective-C singleton that is compatible with ARC?
How do I convert (or create) a singleton class that compiles and behaves correctly when using automatic reference counting (ARC) in Xcode 4.2?
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Copy paste text into iOS simulator
... UI items.
Completely separate from that: your mac has it's own clipboard and content. The Simulator program running on your mac provides the Edit > Paste Text menu item. The program implements that menu item by accessing your mac clipboard and types the text into the simulator as if the user us...
When should I use GET or POST method? What's the difference between them?
...nfuses the concepts a bit. A POST request gets input from the query string and through the request body. A GET request just gets input from the query string. So a POST request is a superset of a GET request; you can use $_GET in a POST request, and it may even make sense to have parameters with the ...
How to add an extra column to a NumPy array
...
I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
In [25]: %timeit b = np.hstac...
How to write inline if statement for print?
...n Python 2.5)
expression_if_true if condition else expression_if_false
And note, that both print a and b = a are statements. Only the a part is an expression. So if you write
print a if b else 0
it means
print (a if b else 0)
and similarly when you write
x = a if b else 0
it means
x = ...
How to convert a std::string to const char* or char*?
...ice that the above is not exception safe. If anything between the new call and the delete call throws, you will leak memory, as nothing will call delete for you automatically. There are two immediate ways to solve this.
boost::scoped_array
boost::scoped_array will delete the memory for you upon go...
Sort array of objects by string property value
...are function body: return a.value - b.value; (ASC)
– Andre Figueiredo
Jan 8 '14 at 12:06
23
@Cerb...
How many levels of pointers can we have?
...
The C standard specifies the lower limit:
5.2.4.1 Translation limits
276 The implementation shall be able to translate and execute at least one program that contains at least one instance of every one of the following limits...