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Mapping two integers to one, in a unique and deterministic way
...sy to define a bijection f : Z -> N, like so:
f(n) = n * 2 if n >= 0
f(n) = -n * 2 - 1 if n < 0
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How is “int* ptr = int()” value initialization not illegal?
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110
int() is a constant expression with a value of 0, so it's a valid way of producing a null pointe...
Python Infinity - Any caveats?
...-a-number (NaN) values from simple arithmetic involving inf:
>>> 0 * float("inf")
nan
Note that you will normally not get an inf value through usual arithmetic calculations:
>>> 2.0**2
4.0
>>> _**2
16.0
>>> _**2
256.0
>>> _**2
65536.0
>>> _**...
Is object empty? [duplicate]
...n-zero value
// that that property is correct.
if (obj.length > 0) return false;
if (obj.length === 0) return true;
// If it isn't an object at this point
// it is empty, but it can't be anything *but* empty
// Is it empty? Depends on your application.
if (typeof...
Modifying a subset of rows in a pandas dataframe
...fy this DataFrame (or create a copy) so that B is always NaN whenever A is 0. How would I achieve that?
5 Answers
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What's the fastest way to loop through an array in JavaScript?
...yntactically obvious).
A standard for-loop with length caching
var i = 0, len = myArray.length;
while (i < len) {
// your code
i++
}
I would say, this is definitely a case where I applaud JavaScript engine developers. A runtime should be optimized for clarity, not cle...
UITableView - scroll to the top
...e top. But I cannot guarantee that the first object is going to be section 0, row 0. May be that my table view will start from section number 5.
...
Can a class member function template be virtual?
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answered Mar 1 '10 at 8:52
sbisbi
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How to draw a rounded Rectangle on HTML Canvas?
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50
The HTML5 canvas doesn't provide a method to draw a rectangle with rounded corners.
How about u...
Formatting a number with exactly two decimals in JavaScript
...ich rounds my numbers to two decimal places. But I get numbers like this: 10.8, 2.4, etc. These are not my idea of two decimal places so how I can improve the following?
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