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How to check if object (variable) is defined in R?
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heh. Happens to me all the time when I am testing out examples before posting, Gavin or Josh have already answered it.
– Maiasaura
Feb 20 '12 at 22:17
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setTimeout / clearTimeout problems
...nswered Jul 31 '17 at 21:45
zero_coolzero_cool
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Why can I initialize a List like an array in C#?
... has a method named Add(...)
What happens is the default constructor is called, and then Add(...) is called for each member of the initializer.
Thus, these two blocks are roughly identical:
List<int> a = new List<int> { 1, 2, 3 };
And
List<int> temp = new List<int>();
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check if variable is dataframe
...rame
Yes: isinstance(x, pd.DataFrame)
And don't even think about
if obj.__class__.__name__ = 'DataFrame':
expect_problems_some_day()
isinstance handles inheritance (see What are the differences between type() and isinstance()?). For example, it will tell you if a variable is a string (eithe...
.NET 4.0 has a new GAC, why?
... Global Assembly Cache (GAC), you will have to manage each of them individually.
In .NET Framework 4.0, the GAC went through a few changes. The GAC was split into two, one for each CLR.
The CLR version used for both .NET Framework 2.0 and .NET Framework 3.5 is CLR 2.0. There was no need in the prev...
Getting value of public static final field/property of a class in Java via reflection
...t(null);
Exception handling is left as an exercise for the reader.
Basically you get the field like any other via reflection, but when you call the get method you pass in a null since there is no instance to act on.
This works for all static fields, regardless of their being final. If the field ...
How do I check if a string is unicode or ascii?
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In Python 3, all strings are sequences of Unicode characters. There is a bytes type that holds raw bytes.
In Python 2, a string may be of type str or of type unicode. You can tell which using code something like this:
def whatisthis(s):...
What is Prefix.pch file in Xcode?
...uestion has been already answered in thread I'm linking below. It contains all the information you need as well as useful comments.
Is it OK to remove Prefix.pch file from the Xcode project?
share
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Get selected subcommand with argparse
...s:
>>> parser = argparse.ArgumentParser()
>>> parser.add_argument('-g', '--global')
>>> subparsers = parser.add_subparsers(dest="subparser_name") # this line changed
>>> foo_parser = subparsers.add_parser('foo')
>>> foo_parser.add_argument('-c', '--count...
Python Threading String Arguments
...t list
processThread.start()
If you notice, from the stack trace: self.__target(*self.__args, **self.__kwargs)
The *self.__args turns your string into a list of characters, passing them to the processLine
function. If you pass it a one element list, it will pass that element as the first argum...