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In Python, what is the difference between “.append()” and “+= []”?
...d will add one item to the list, while += will copy all elements of right-hand-side list into the left-hand-side list.
Update: perf analysis
Comparing bytecodes we can assume that append version wastes cycles in LOAD_ATTR + CALL_FUNCTION, and += version -- in BUILD_LIST. Apparently BUILD_LIST outw...
How do I specify a pointer to an overloaded function?
...
@BenVoigt Hmm, I tested this on vs2010 and couldn't find a case where the static_cast wouldn't catch the problem at compile time. It gave a C2440 with "None of the functions with this name in scope match the target type". Can you clarify?
–...
Turning multi-line string into single comma-separated
...
You can use awk and sed:
awk -vORS=, '{ print $2 }' file.txt | sed 's/,$/\n/'
Or if you want to use a pipe:
echo "data" | awk -vORS=, '{ print $2 }' | sed 's/,$/\n/'
To break it down:
awk is great at handling data broken down into fi...
Javascript seconds to minutes and seconds
...seconds by 60 (60 seconds/minute):
var minutes = Math.floor(time / 60);
And to get the remaining seconds, multiply the full minutes with 60 and subtract from the total seconds:
var seconds = time - minutes * 60;
Now if you also want to get the full hours too, divide the number of total seconds...
Rolling median algorithm in C
...ial window of values, then perform a binary search to insert the new value and remove the existing one at each iteration.
1...
How do I trim whitespace?
Is there a Python function that will trim whitespace (spaces and tabs) from a string?
15 Answers
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Whitespace Matching Regex - Java
...is strictly required to meet UTS#18’s RL1.2! What it does have is not standards-conforming, alas.
Unicode defines 26 code points as \p{White_Space}: 20 of them are various sorts of \pZ GeneralCategory=Separator, and the remaining 6 are \p{Cc} GeneralCategory=Control.
White space is a pretty s...
How do I find duplicates across multiple columns?
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Duplicated id for pairs name and city:
select s.id, t.*
from [stuff] s
join (
select name, city, count(*) as qty
from [stuff]
group by name, city
having count(*) > 1
) t on s.name = t.name and s.city = t.city
...
What is the maximum possible length of a .NET string?
...owhere near that. Since no single object in a .NET program may be over 2GB and the string type uses UTF-16 (2 bytes for each character), the best you could do is 1,073,741,823, but you're not likely to ever be able to allocate that on a 32-bit machine.
This is one of those situations where "If you ...
GCC compile error with >2 GB of code
...+
1/10.*s.x14*s.x15*csc[49302] - 3/5.*s.x14*s.x15*csc[49303] -...
and
double csc19295 = + s.ds0*s.ds1*s.ds2 * ( -
32*s.x12pow2*s.x15*s.x34*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.mbpow2*s.mWpowinv2 -
32*s.x12pow2*s.x15*s.x35*s.x45*s.mWpowinv2 -...
rig...