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Rename specific column(s) in pandas
I've got a dataframe called data . How would I rename the only one column header? For example gdp to log(gdp) ?
5 Answe...
Database, Table and Column Naming Conventions? [closed]
... for Primary Key Columns, Hungarian-esque Constraint Prefixes and worst of all SPACES " " for multi-word table names. Additionally system tables for SQLServer use plurals so it seems AdventureWorks was the black sheep in this bunch.
– Marcus Pope
Mar 20 '12 at...
Select distinct values from a table field
...ant any ordering to be applied to a query, not even the default ordering, call order_by() with no parameters.
and distinct() in the note where it discusses issues with using distinct() with ordering.
To query your DB, you just have to call:
models.Shop.objects.order_by().values('city').distinct(...
How to display all methods of an object?
I want to know how to list all methods available for an object like for example:
8 Answers
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How do I override __getattr__ in Python without breaking the default behavior?
I want to override the __getattr__ method on a class to do something fancy but I don't want to break the default behavior.
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Returning binary file from controller in ASP.NET Web API
...rn result;
}
A few things to note about the stream used:
You must not call stream.Dispose(), since Web API still needs to be able to access it when it processes the controller method's result to send data back to the client. Therefore, do not use a using (var stream = …) block. Web API will di...
What is the syntax rule for having trailing commas in tuple definitions?
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In all cases except the empty tuple the comma is the important thing. Parentheses are only required when required for other syntactic reasons: to distinguish a tuple from a set of function arguments, operator precedence, or to a...
Implementing slicing in __getitem__
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The __getitem__() method will receive a slice object when the object is sliced. Simply look at the start, stop, and step members of the slice object in order to get the components for the slice.
>>> class C(object):
......
What does the Reflect object do in JavaScript?
...ble:
ES6 spec, Reflection
MDN Reflect (including details and examples to all of its methods)
Original answer (for (historic) understanding and extra examples):
The Reflection proposal seems to have progressed to the Draft ECMAScript 6 Specification. This document currently outlines the Reflect...
How to open, read, and write from serial port in C?
...en), and just copy and paste the bits needed into each project.
You must call cfmakeraw on a tty obtained from tcgetattr. You cannot zero-out a struct termios, configure it, and then set the tty with tcsetattr. If you use the zero-out method, then you will experience unexplained intermittent failur...