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Is pass-by-value a reasonable default in C++11?
In traditional C++, passing by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory ma...
Access to Modified Closure (2)
This is an extension of question from Access to Modified Closure . I just want to verify if the following is actually safe enough for production use.
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In R, how to get an object's name after it is sent to a function?
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The old deparse-substitute trick:
a<-data.frame(x=1:10,y=1:10)
test<-function(z){
mean.x<-mean(z$x)
nm <-deparse(substitute(z))
print(nm)
return(mean.x)}
test(a)
#[1] "a" ... this is the side-effect of the print()...
AngularJS validation with no enclosing
Is it possible in Angular to validate a single, isolated <input> in a similar way the forms are validated? I'm thinking about something like this:
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printf format specifiers for uint32_t and size_t
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Sounds like you're expecting size_t to be the same as unsigned long (possibly 64 bits) when it's actually an unsigned int (32 bits). Try using %zu in both cases.
I'm not entirely certain though.
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What does “all” stand for in a makefile?
I read some tutorials concerning Makefiles but for me it is still unclear for what the target "all" stands for and what it does.
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Best way to check if a Data Table has a null value in it
what is the best way to check if a Data Table has a null value in it ?
6 Answers
6
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Is having an 'OR' in an INNER JOIN condition a bad idea?
In trying to improve the speed of an immensely slow query (several minutes on two tables with only ~50,000 rows each, on SQL Server 2008 if it matters), I narrowed down the problem to an OR in my inner join, as in:
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Merge Images Side by Side(Horizontally)
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ImageMagick ships with the montage utility. Montage will append each image side-by-side allowing you to adjust spacing between each image (-geometry), and the general layout (-tile).
montage [0-5].png -tile 5x1 -geometry +0+0 out.png
Other examples can be ...
Android: When is onCreateOptionsMenu called during Activity lifecycle?
I put a couple of breakpoints in onCreate (one at the beginning, and one at the end of the method), and I also put one at the beginning of onCreateOptionsMenu . The onCreate method is called first, and before it finishes onCreateOptionsMenu is called.
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