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How to get first element in a list of tuples?
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do you mean something like this?
new_list = [ seq[0] for seq in yourlist ]
What you actually have is a list of tuple objects, not a list of sets (as your original question implied). If it is actually a list of sets, then there is no first element because set...
How do I remove code duplication between similar const and non-const member functions?
... C &>(*this).get());
}
char c;
};
The two casts and function call may be ugly but it's correct. Meyers has a thorough explanation why.
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How to use a class from one C# project with another C# project
...that you wish to access directly must have a sufficient access level: typically this means they must be made public.
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Do you need text/javascript specified in your tags?
...tribute is optional. Since Netscape 2, the default programming language in all browsers has been JavaScript. In XHTML, this attribute is required and unnecessary. In HTML, it is better to leave it out. The browser knows what to do.
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What is the difference between “ is None ” and “ ==None ”
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class Foo:
def __eq__(self,other):
return True
foo=Foo()
print(foo==None)
# True
print(foo is None)
# False
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Linq Syntax - Selecting multiple columns
...method chaining. The method chaining equivalent would be:-
var employee = _db.EMPLOYEEs
.Where(x => x.EMAIL == givenInfo || x.USER_NAME == givenInfo)
.Select(x => new { x.EMAIL, x.ID });
AFAIK, the declarative LINQ syntax is converted to a method call chain similar to this when it i...
How do I replace NA values with zeros in an R dataframe?
...then assign it to the location/name on the left. In this case, we aren't really "doing" anything - just making zeroes. The left side is saying: look at the d object, inside the d object (the square brackets), find all the elements that return TRUE (is.na(d) returns a logical for each element). Once...
Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
I have installed MySQL server and trying to connect to it, but getting the error:
18 Answers
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Is there an alternative sleep function in C to milliseconds?
...s defined usleep(), so this is available on Linux:
int usleep(useconds_t usec);
DESCRIPTION
The usleep() function suspends execution of the calling thread for
(at least) usec microseconds. The sleep may be lengthened slightly by
any system activity or by the tim...
Removing an item from a select box
...ray $("#myselect").removeOption(["myselect_1", "myselect_2"]);
To remove all options, you can do $("#myselect").removeOption(/./);.
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