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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...
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How to deal with INSTALL_PARSE_FAILED_INCONSISTENT_CERTIFICATES without uninstall?

I tried to reinstall an apk 16 Answers 16 ...
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Django set field value after a form is initialized

...value after the form was submitted, you can use something like: if form.is_valid(): form.cleaned_data['Email'] = GetEmailString() Check the referenced docs above for more on using cleaned_data share | ...
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Display block without 100% width

... gets positioned before the last span. Guess one solution would be to make all child elements in the li float. – Staffan Estberg Oct 3 '12 at 17:01 ...
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Co-variant array conversion from x to y may cause run-time exception

...js[0] = new Foo(); // again legal, with runtime exception In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
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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...
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Database sharding vs partitioning

...databases. Sharding is one specific type of partitioning, part of what is called horizontal partitioning. Here you replicate the schema across (typically) multiple instances or servers, using some kind of logic or identifier to know which instance or server to look for the data. An identifier of th...
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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...
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Why can't I use the 'await' operator within the body of a lock statement?

The await keyword in C# (.NET Async CTP) is not allowed from within a lock statement. 8 Answers ...
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Cast Object to Generic Type for returning

...> T convertInstanceOfObject(java.lang.Object); Code: 0: aload_0 1: areturn 2: astore_1 3: aconst_null 4: areturn Exception table: from to target type 0 1 2 Class java/lang/ClassCastException public static void main(java...