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parseInt vs unary plus, when to use which?
...er for a more complete set of cases
Well, here are a few differences I know of:
An empty string "" evaluates to a 0, while parseInt evaluates it to NaN. IMO, a blank string should be a NaN.
+'' === 0; //true
isNaN(parseInt('',10)); //true
The unary + acts more like parseFloat ...
Update git commit author date when amending
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FTR, looks like on OS X, date doesn't know -R. Using date without options did the job anyway
– ksol
Feb 2 '12 at 10:29
7
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How to write LaTeX in IPython Notebook?
...doing, found a better solution with some more searching, IPython notebooks now have a %%latex magic that makes the whole cell Latex without the $$ wrapper for each line.
Refer notebook tour for Rich Display System
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Difference between freeze and seal
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FWIW, frozen and sealed objects are now faster than their unfrozen and unsealed counterparts in Chrome Canary v43.0.2317.0.
– llambda
Feb 28 '15 at 22:57
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Fastest way to determine if an integer is between two integers (inclusive) with known sets of values
...does a comparison of resulting assembler and profiling info). For all we know, the OP's compiler may render the OP's code with a single branch opcode...
– Oliver Charlesworth
Jun 13 '13 at 19:50
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Get month name from number
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import datetime
mydate = datetime.datetime.now()
mydate.strftime("%B")
Returns: December
Some more info on the Python doc website
[EDIT : great comment from @GiriB] You can also use %b which returns the short notation for month name.
mydate.strftime("%b")
For...
Computational complexity of Fibonacci Sequence
I understand Big-O notation, but I don't know how to calculate it for many functions. In particular, I've been trying to figure out the computational complexity of the naive version of the Fibonacci sequence:
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Measuring execution time of a function in C++
...5;
}
}
int main()
{
auto t1 = std::chrono::high_resolution_clock::now();
function();
auto t2 = std::chrono::high_resolution_clock::now();
auto duration = std::chrono::duration_cast<std::chrono::microseconds>( t2 - t1 ).count();
std::cout << duration;
return...
Current time in microseconds in java
...ave System.nanoTime(), but that just gives an offset from some previously known time. So whilst you can't take the absolute number from this, you can use it to measure nanosecond (or higher) precision.
Note that the JavaDoc says that whilst this provides nanosecond precision, that doesn't mean nano...
Does Dart support enumerations?
... constants within the class are compile time constants, and this class can now be used in, for example, switch statements:
var a = Fruit.APPLE;
switch (a) {
case Fruit.APPLE:
print('Yes!');
break;
}
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