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How to truncate milliseconds off of a .NET DateTime
...is between 50% and about 100% depending on the runtime; net 4.7.2: 0.35µs vs 0.62 µs and core 3.1: 0.18 µs vs 0.12 µs that's micro-seconds (10^-6 seconds)
– juwens
Feb 3 at 15:55
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Using column alias in WHERE clause of MySQL query produces an error
...ing HAVING instead may do the work. Make sure to give a read at this WHERE vs HAVING though.
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DistutilsOptionError: must supply either home or prefix/exec-prefix — not both
... say solution; perhaps it's just another motivation to meticulously use venvs...
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What is the rationale behind having companion objects in Scala?
... Int) = {
new AlternativeThing(i)
}
}
// somewhere else you can
val vs = AbstractClass("asdf") // gives you the RealThing wrapped over string
val vi = AbstractClass(123) // gives you AlternativeThing wrapped over int
I wouldn't call the object/base class AbstractXxxxx because it doesn't l...
How to split a delimited string into an array in awk?
...etter than '\|', in some cases, especially as some variant of regexp (perl vs grep vs .. others?) can have "|" interepreted literally and "\|" seen as regex separator, instead of the opposite... ymmv
– Olivier Dulac
Dec 5 '19 at 9:16
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how to set radio option checked onload with jQuery
...ead of attr() for this kind of thing. For explanation, see the "Attributes vs. Properties" section here: api.jquery.com/prop. Also there's no need for the extra filter, you can just combine the 2 selectors e.g. $("input[name=gender][value=Male]").prop("checked", true);
– jackoc...
How do I find the .NET version?
... of the .NET framework that version of the compiler targets. - If you have VS2005 & VS2008 installed the different versions of CSC will report different versions.
– Matt Lacey
Oct 14 '09 at 10:37
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Drop data frame columns by name
...cars
colnames(dat)
# [1] "mpg" "cyl" "disp" "hp" "drat" "wt" "qsec" "vs" "am" "gear"
# [11] "carb"
dat[,c("mpg","cyl","wt")] <- list(NULL)
colnames(dat)
# [1] "disp" "hp" "drat" "qsec" "vs" "am" "gear" "carb"
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val-mutable versus var-immutable in Scala
...concurrency. And while we're at it, note the preferred use of synchronised vs @volatile vs something like AtomicReference: three tools
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What is more efficient? Using pow to square or just multiply it with itself?
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I tested the performance difference between x*x*... vs pow(x,i) for small i using this code:
#include <cstdlib>
#include <cmath>
#include <boost/date_time/posix_time/posix_time.hpp>
inline boost::posix_time::ptime now()
{
return boost::posix_time::micro...