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Converting a Pandas GroupBy output from Series to DataFrame
...taFrame. It has a hierarchical index, though:
In [19]: type(g1)
Out[19]: pandas.core.frame.DataFrame
In [20]: g1.index
Out[20]:
MultiIndex([('Alice', 'Seattle'), ('Bob', 'Seattle'), ('Mallory', 'Portland'),
('Mallory', 'Seattle')], dtype=object)
Perhaps you want something like this?
In ...
Large-scale design in Haskell? [closed]
...
I talk a bit about this in Engineering Large Projects in Haskell and in the Design and Implementation of XMonad. Engineering in the large is about managing complexity. The primary code structuring mechanisms in Haskell for managing complexity are:
The type system
Use the type system to ...
What is BSON and exactly how is it different from JSON?
I am just starting out with MongoDB and one of the things that I have noticed is that it uses BSON to store data internally. However the documentation is not exactly clear on what BSON is and how it is used in MongoDB. Can someone explain it to me, please?
...
DTO and DAO concepts and MVC [closed]
1) Why do we use DTO and DAO , and when should we use them. I am developing a GUI Java software to do with inserting, editing, deleting data. But I am struggling to distinguish between DTO/DAO and Model , View , Controller (MVC) Structure? Are they similar, which is better to use when i...
How to implement a many-to-many relationship in PostgreSQL?
...ct is hardly unique (not a good "natural key"). Also, enforcing uniqueness and referencing the column in foreign keys is typically cheaper with a 4-byte integer (or even an 8-byte bigint) than with a string stored as text or varchar.
Don't use names of basic data types like date as identifiers. Whi...
Max parallel http connections in a browser?
...s specifically related to HTTP 1.1; other protocols have separate concerns and limitations (i.e., SPDY, TLS, HTTP 2).
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What is the main difference between Inheritance and Polymorphism?
... was presented with this question in an end of module open book exam today and found myself lost. I was reading Head first Java and both definitions seemed to be exactly the same. I was just wondering what the MAIN difference was for my own piece of mind. I know there are a number of similar questi...
NHibernate.MappingException: No persister for: XYZ
Now, before you say it: I did Google and my hbm.xml file is an Embedded Resource.
16 Answers
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Why is 'this' a pointer and not a reference?
I was reading the answers to this question C++ pros and cons and got this doubt while reading the comments.
2 Answers
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Creating instance of type without default constructor in C# using reflection
...ance without calling a constructor. I found this class by using Reflector and digging through some of the core .Net serialization classes.
I tested it using the sample code below and it looks like it works great:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Te...