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How to print a groupby object
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Call list() on the GroupBy object
print(list(df.groupby('A')))
gives you:
[('one', A B
0 one 0
1 one 1
5 one 5), ('three', A B
3 three 3
4 three 4), ('two', A B
2 two 2)]
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How do I define global variables in CoffeeScript?
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Since coffee script has no var statement it automatically inserts it for all variables in the coffee-script, that way it prevents the compiled JavaScript version from leaking everything into the global namespace.
So since there's no way to make something "leak" into the glo...
Performance surprise with “as” and nullable types
... is tricky due to possible boxed enum types. The JIT compiler generates a call to a CLR helper function named JIT_Unbox_Nullable to get the job done. This is a general purpose function for any value type, lots of code there to check types. And the value is copied. Hard to estimate the cost since...
Custom Compiler Warnings
... Obsolete
attribute, the compiler issues a
warning or an error. Specifically, the
compiler issues a warning if no error
parameter is provided, or if the error
parameter is provided and has the
value false. The compiler issues an
error if the error parameter is
specified and has the v...
What is the difference between Builder Design pattern and Factory Design pattern?
...y method pattern requires the entire object to be built in a single method call, with all the parameters passed in on a single line. The final object will be returned.
A builder pattern, on the other hand, is in essence a wrapper object around all the possible parameters you might want to pass into...
How to negate a method reference predicate
...aster. It eliminates a stream creation, it eliminates using another method call (negative function for predicate), and it eliminates a temporary accumulator list/counter. So a few things that are saved by the last construct that might make it faster.
I do think it is simpler and nicer though, even...
Ruby on Rails form_for select field with class
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Right on the money, thank you so much, that did the trick! I knew that it had to be something simple and of course it was.
– Patrick
Nov 2 '10 at 21:34
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When exactly is it leak safe to use (anonymous) inner classes?
...s when a class definition is contained within another class. There are basically two types: Static Nested Classes and Inner Classes. The real difference between these are:
Static Nested Classes:
Are considered "top-level".
Do not require an instance of the containing class to be constructed.
M...
Set custom attribute using JavaScript
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Use the setAttribute method:
document.getElementById('item1').setAttribute('data', "icon: 'base2.gif', url: 'output.htm', target: 'AccessPage', output: '1'");
But you really should be using data followed with a dash and with its property, like:
<li ... data-icon="base....
What are the pros and cons of the leading Java HTML parsers? [closed]
... degree forgiving and lenient with non-wellformed HTML ("tagsoup"), like JTidy, NekoHTML, TagSoup and HtmlCleaner. You usually use this kind of HTML parsers to "tidy" the HTML source (e.g. replacing the HTML-valid <br> by a XML-valid <br />), so that you can traverse it "the usual way" u...