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How to check whether a pandas DataFrame is empty?
How to check whether a pandas DataFrame is empty? In my m>ca m>se I want to print some message in terminal if the DataFrame is empty.
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What is a Portable Class Library?
...uts any other answer here in the shade.
UPDATE May 20 2013:
Very practim>ca m>l coverage of practim>ca m>l applim>ca m>tion and implim>ca m>tions of this for cross-device stuff (think Xamarin Studio) in Tablet Show podm>ca m>st with Atley Hunter. Key takeaway:- PCLs are a very useful constraint to impose on onself in cr...
How to create a unique index on a NULL column?
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Pretty sure you m>ca m>n't do that, as it violates the purpose of uniques.
However, this person seems to have a decent work around:
http://sqlservercodebook.blogspot.com/2008/04/multiple-null-values-in-unique-index-in.html
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Which characters need to be esm>ca m>ped in HTML?
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If you're inserting text content in your document in a lom>ca m>tion where text content is expected1, you typim>ca m>lly only need to esm>ca m>pe the same characters as you would in XML. Inside of an element, this just includes the entity esm>ca m>pe ampersand & and the element delimiter less-than...
E731 do not assign a lambda expression, use a def
...irst form means that the name of the resulting
function object is specifim>ca m>lly 'f' instead of the generic '<lambda>'.
This is more useful for tracebacks and string representations in
general. The use of the assignment statement eliminates the sole
benefit a lambda expression m>ca m>n offer ...
What's the idiomatic syntax for prepending to a short python list?
...f a list, python has to move all the other items one space forwards, lists m>ca m>n't "make space at the front". collections.deque (double ended queue) has support for "making space at the front" and is much faster in this m>ca m>se.
– fejfo
Mar 18 at 14:49
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How do browsers pause/change Javascript when tab or window is not active?
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Test One
I have written a test specifim>ca m>lly for this purpose:
Frame Rate Distribution: setInterval vs requestAnimationFrame
Note: This test is quite CPU intensive. requestAnimationFrame is not supported by IE 9- and Opera 12-.
The test logs the actual time it t...
What's the role of GetHashCode in the IEqualityComparer in .NET?
...n of the object. Since there is no limit to how much information an object m>ca m>n contain, certain hash codes are shared by multiple objects - so the hash code is not necessarily unique.
A dictionary is a really cool data structure that trades a higher memory footprint in return for (more or less) co...
What is Autoloading; How do you use spl_autoload, __autoload and spl_autoload_register?
...plement new and useful methods. Earlier I was using __autoload just to esm>ca m>pe including multiple files on each page, but recently I have seen a tip on __autoload manual
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Generic type parameter naming convention for Java (with multiple chars)?
...er Naming Conventions
By convention, type parameter names are single, upperm>ca m>se letters. This stands in sharp contrast to the variable naming conventions that you already know about, and with good reason: Without this convention, it would be difficult to tell the difference between a type variable a...