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pandas three-way joining multiple dataframes on columns
...on. If I have more than a handful of dataframes, I'd put them in a list like this (generated via list comprehensions or loops or whatnot):
dfs = [df0, df1, df2, dfN]
Assuming they have some common column, like name in your example, I'd do the following:
df_final = reduce(lambda left,right: pd.m...
What's the difference between dynamic (C# 4) and var?
I had read a ton of articles about that new keyword that is shipping with C# v4, but I couldn't make out the difference between a "dynamic" and "var".
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How to merge the current branch into another branch
I have two branches, master and dev. I always work on dev and only check code into the master branch once it's been approved for production use. When I do so, I have to do the following:
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Can you find all classes in a package using reflection?
Is it possible to find all classes or interfaces in a given package? (Quickly looking at e.g. Package , it would seem like no.)
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Create a list from two object lists with linq
...e removed. If you don't specify a comparer in the Union extension method like in my example, it will use the default Equals and GetHashCode methods in your Person class. If you for example want to compare persons by comparing their Name property, you must override these methods to perform the compar...
Install NPM into home directory with distribution nodejs package (Ubuntu)
I'd like to use the distribution Node.js packages (or the chris-lea ppa for more recent releases) but install NPM to my home directory.
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PowerShell and the -contains operator
...e string and is used to search collections.
From the documentation you linked to:
-Contains
Description: Containment operator. Tells whether a collection of reference values includes a single test value.
In the example you provided you're working with a collection containing just one string...
BCL (Base Class Library) vs FCL (Framework Class Library)
...(BCL) is literally that, the base. It contains basic, fundamental types like System.String and System.DateTime.
The Framework Class Library (FCL) is the wider library that contains the totality: ASP.NET, WinForms, the XML stack, ADO.NET and more. You could say that the FCL includes the BCL.
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Limits of Nat type in Shapeless
...lculations on type level, e.g. append a list of N elements to a list of K elements and get back a list that is known at compile time to have N+K elements.
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Nullable Foreign Key bad practice?
Let's say you have a table Orders with a foreign key to a Customer Id. Now, suppose you want to add an Order without a Customer Id, (whether that should be possible is another question) you would have to make the foreign key NULL... Is that bad practice or would you rather work with a link table bet...