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How do I check that a number is float or integer?
How to find that a number is float or integer ?
44 Answers
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How to tell if a string is not defined in a Bash shell script
If I want to check for the null string I would do
12 Answers
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How can I add a custom HTTP header to ajax request with js or jQuery?
Does anyone know how to add or create a custom HTTP header using JavaScript or jQuery?
9 Answers
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To find whether a column exists in data frame or not
... dat and that your column name to check is "d", you can use the %in% operator:
if("d" %in% colnames(dat))
{
cat("Yep, it's in there!\n");
}
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How do I test a private function or a class that has private methods, fields or inner classes?
... unit test (using xUnit) a class that has internal private methods, fields or nested classes? Or a function that is made private by having internal linkage ( static in C/C++) or is in a private ( anonymous ) namespace?
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What should main() return in C and C++?
What is the correct (most efficient) way to define the main() function in C and C++ — int main() or void main() — and why? And how about the arguments?
If int main() then return 1 or return 0 ?
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Java synchronized static methods: lock on object or class
...Since a static method has no associated object, will the synchronized keyword lock on the class, instead of the object?
Yes. :)
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MySQL WHERE: how to write “!=” or “not equals”?
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The != operator most certainly does exist! It is an alias for the standard <> operator.
Perhaps your fields are not actually empty strings, but instead NULL?
To compare to NULL you can use IS NULL or IS NOT NULL or the null safe e...
Should I return EXIT_SUCCESS or 0 from main()?
...g conflicting answers: should the main routine of a C++ program return 0 or EXIT_SUCCESS ?
8 Answers
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Java logical operator short-circuiting
Which set is short-circuiting, and what exactly does it mean that the complex conditional expression is short-circuiting?
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