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Is there an R function for finding the index of an element in a vector?
..., but that seems excessively inefficient. Is there a more direct way to do it?
4 Answers
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How different is Objective-C from C++? [closed]
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Short list of some of the major differences:
C++ allows multiple inheritance, Objective-C doesn't.
Unlike C++, Objective-C allows method parameters to be named and the method signature includes only the names and types of the parameters and return type (see bbum's and Chuck's comments below). I...
How to change the type of a field?
I am trying to change the type of a field from within the mongo shell.
14 Answers
14
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Listview Scroll to the end of the list after updating the list
...he bottom, after I have updated the listview by using listAdapter, so that it displays the last element entered in the list. How can I do this ?
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Test if string is a number in Ruby on Rails
...is_number? string
true if Float(string) rescue false
end
And then call it like this:
my_string = '12.34'
is_number?( my_string )
# => true
Extend String Class.
If you want to be able to call is_number? directly on the string instead of passing it as a param to your helper function, then ...
How to make HTML Text unselectable [duplicate]
I would like to add text to my webpage as a label and make it unselectable.
4 Answers
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How do I verify a method was called exactly once with Moq?
How do I verify a method was called exactly once with Moq? The Verify() vs. Verifable() thing is really confusing.
3 A...
Why do we need C Unions?
... and floats:
union
{
int i;
float f;
} u;
// Convert floating-point bits to integer:
u.f = 3.14159f;
printf("As integer: %08x\n", u.i);
Although this is technically undefined behavior according to the C standard (you're only supposed to read the field which was most recently written), it wil...
How do I calculate the date in JavaScript three months prior to today?
... that one month ago means the same day of the month on the previous month citation needed. But more than half the time, that is 31 days ago, not 30. And if today is the 31st of the month (and it isn't August or Decemeber), that day of the month doesn't exist in the previous month.
Interestingly, ...
Open Cygwin at a specific folder
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When you install Cygwin (or if you’ve already installed it, download it again and start setup again to run an update), make sure that you select the chere package under the "Shells" category.
After Cygwin is launched, open up a Cygwin terminal (as an administrator) and type the c...