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Get statistics for each group (such as count, mean, etc) using pandas GroupBy?
...instead of a Series) so you can do:
df.groupby(['col1', 'col2']).size().reset_index(name='counts')
If you want to find out how to calculate the row counts and other statistics for each group continue reading below.
Detailed example:
Consider the following example dataframe:
In [2]: df
Out...
Assigning code to a variable
... editor after snippets, if snippets enabled
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Transpose/Unzip Function (inverse of zip)?
...gister(abc.Sequence, transpose_finite_iterable)
transpose.register(abc.Set, transpose_finite_iterable)
which can be considered as its own inverse (mathematicians call this kind of functions "involutions") in class of binary operators over finite non-empty iterables.
As a bonus of singledisp...
“npm config set registry https://registry.npmjs.org/” is not working in windows bat file
...guration for npm.
The correct command for changing registry is
npm config set registry <registry url>
you can find more information with npm help config command, also check for privileges when and if you are running .bat files this way.
...
How to sort a dataframe by multiple column(s)
...nough: dd[ order(-dd[,4], dd[,1]), ], but can't use with for name-based subsetting.
– Dirk Eddelbuettel
Oct 21 '12 at 14:34
...
Class does not implement its superclass's required members
...ializer must be marked using Swift's required keyword.
Swift has a special set of inheritance rules regarding init methods.
The tl;dr is this:
If you implement any initializers, you are no longer inheriting any of the superclass's designated initializers.
The only initializers, if any, that you w...
How does one parse XML files? [closed]
...
Use a good XSD Schema to create a set of classes with xsd.exe and use an XmlSerializer to create a object tree out of your XML and vice versa. If you have few restrictions on your model, you could even try to create a direct mapping between you model classes ...
What is the difference between Polymer elements and AngularJS directives?
...s entire architecture stack:
RED layer: We get tomorrow's web through a set of polyfills. Keep in mind, those libraries go away over time as browsers adopt the new APIs.
YELLOW layer: Sprinkle in some sugar with polymer.js. This layer is our opinion on how to use the spec'd APIs, together. It al...
Split List into Sublists with LINQ
... return !done;
}
public void Reset()
{
// per http://msdn.microsoft.com/en-us/library/system.collections.ienumerator.reset.aspx
throw new NotSupportedException();
}
}
...
Create a pointer to two-dimensional array
...its underlying data is made of other arrays), which consists of boundaries set by the array beyond the first dimension.
This 'partition' logic cannot exist within a pointer unless we specify it:
int a[4][5][95][8];
int (*p)[5][95][8];
p = a; // p = *a[0] // p = a+0
Otherwise, the meaning of th...