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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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Programmatically change the src of an img tag

...ng an image src (especial when you're using elements that have IDs), you really should try to avoid jQuery, since the call is so much slower than the pure JS call – Brian Leishman Apr 8 '15 at 13:36 ...
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How to declare a global variable in JavaScript?

...s available only in browsers. Could you edit you answer to make it work in all environments? See How to get the global object in JavaScript? – Michał Perłakowski Nov 30 '16 at 15:50 ...
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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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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 ...
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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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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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Remove excess whitespace from within a string

I receive a string from a database query, then I remove all HTML tags, carriage returns and newlines before I put it in a CSV file. Only thing is, I can't find a way to remove the excess white space from between the strings. ...
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How to POST JSON Data With PHP cURL?

...re indicating Content-Type:application/json, but you are not json-encoding all of the POST data -- only the value of the "customer" POST field. Instead, do something like this: $ch = curl_init( $url ); # Setup request to send json via POST. $payload = json_encode( array( "customer"=> $data ) );...
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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 ...