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PHP global in functions
... to it. It is only when I look at the function body that I learn I have to set the environment into a certain state.
If your function requires arguments to run, make them explicit and pass them in:
function fn($arg1, $arg2)
{
// do sth with $arguments
}
clearly conveys from the signature wha...
valueOf() vs. toString() in Javascript
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When should the volatile keyword be used in C#?
... std::cout << j;
}
Using the standard optimised (release) compiler settings, the compiler creates the following assembler (IA32):
void main()
{
00401000 push ecx
int j = 0;
00401001 xor ecx,ecx
for (int i = 0 ; i < 100 ; ++i)
00401003 xor eax,eax
0040100...
How to check if one of the following items is in a list?
...L2 = [1,2]
>>> [i for i in L1 if i in L2]
[2]
>>> S1 = set(L1)
>>> S2 = set(L2)
>>> S1.intersection(S2)
set([2])
Both empty lists and empty sets are False, so you can use the value directly as a truth value.
...
When and why will a compiler initialise memory to 0xCD, 0xDD, etc. on malloc/free/new/delete?
...
It's compiler and OS specific, Visual studio sets different kinds of memory to different values so that in the debugger you can easily see if you have overun into into malloced memory, a fixed array or an uninitialised object.
Somebody will post the details while I am g...
Is Java's assertEquals method reliable?
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What is the difference between Digest and Basic Authentication?
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What is the difference between gravity and layout_gravity in Android?
I know we can set the following values to the android:gravity and android:layout_gravity properties:
20 Answers
...
How can I get the browser's scrollbar sizes?
...ndChild (inner);
document.body.appendChild (outer);
var w1 = inner.offsetWidth;
outer.style.overflow = 'scroll';
var w2 = inner.offsetWidth;
if (w1 == w2) w2 = outer.clientWidth;
document.body.removeChild (outer);
return (w1 - w2);
};
...
python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B
...is takes the last. Not the maximum though:
In [10]: df.drop_duplicates(subset='A', keep="last")
Out[10]:
A B
1 1 20
3 2 40
4 3 10
You can do also something like:
In [12]: df.groupby('A', group_keys=False).apply(lambda x: x.loc[x.B.idxmax()])
Out[12]:
A B
A
1 1 20
2 2 ...