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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...
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
...
“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.
...
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...