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What is the difference between == and Equals() for primitives in C#?
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Short answer:
Equality is complicated.
Detailed answer:
Primitives types override the base object.Equals(object) and return true if the boxed object is of the same type and value. (Note that it will also work for nullable types; non-null nullable type...
How to convert a factor to integer\numeric without loss of information?
...proximately its original numeric
values, as.numeric(levels(f))[f] is
recommended and slightly more
efficient than
as.numeric(as.character(f)).
The FAQ on R has similar advice.
Why is as.numeric(levels(f))[f] more efficent than as.numeric(as.character(f))?
as.numeric(as.character(f)) is...
Can I make git recognize a UTF-16 file as text?
... diff.tool vimdiff # or merge.tool to get merging too!
$ git difftool commit1 commit2
git difftool takes the same arguments as git diff would, but runs a diff program of your choice instead of the built-in GNU diff. So pick a multibyte-aware diff (in my case, vim in diff mode) and just use g...
Specifically, what's dangerous about casting the result of malloc?
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You won't get a compiler error, but a compiler warning. As the sources you cite say (especially the first one), you can get an unpredictable runtime error when using the cast without including stdlib.h.
So the error on your side is not the ...
Stop Excel from automatically converting certain text values to dates
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I have found that putting an '=' before the double quotes will accomplish what you want. It forces the data to be text.
eg. ="2008-10-03",="more text"
EDIT (according to other posts): because of the Excel 2007 bug noted by Jeffiekins one should use the solution proposed by Andrew: "=""20...
How to keep onItemSelected from firing off on a newly instantiated Spinner?
... answered Apr 1 '10 at 17:53
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What is the fastest way to compute sin and cos together?
I would like to compute both the sine and co-sine of a value together (for example to create a rotation matrix). Of course I could compute them separately one after another like a = cos(x); b = sin(x); , but I wonder if there is a faster way when needing both values.
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Foreign key constraint may cause cycles or multiple cascade paths?
...the referential actions. If you can't alter your design (or doing so would compromise things) then you should consider using triggers as a last resort.
FWIW resolving cascade paths is a complex problem. Other SQL products will simply ignore the problem and allow you to create cycles, in which case ...
Why is i++ not atomic?
...ent is performed using i = i + 1. However, this would break the "cultural compatibility" between Java, and C and C++. As well, it would take away a convenient notation which programmers familiar with C-like languages take for granted, giving it a special meaning that applies only in limited circums...
Where do “pure virtual function call” crashes come from?
I sometimes notice programs that crash on my computer with the error: "pure virtual function call".
8 Answers
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