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Add a column to existing table and uniquely number them on MS SQL Server
...be of type IDENTITY (auto-increment), or you want to be specific about the order in which your rows are numbered, you can add a column of type INT NULL and then populate it like this. In my example, the new column is called MyNewColumn and the existing primary key column for the table is called MyP...
Are list-comprehensions and functional functions faster than “for loops”?
...ension, for example, is indeed faster, it would be a much better option in order to avoid lags (Despite the visual complexity of the code).
Chances are, if code like this isn't already fast enough when written in good non-"optimized" Python, no amount of Python level micro optimization is going to...
Replacement for “rename” in dplyr
...onious solution but this works and preserves all columns (though not their order). disp does not get duplicated.
– farnsy
Aug 22 '14 at 3:38
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Why does Python code use len() function instead of a length method?
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len, str, etc. can be used with higher-order functions like map, reduce, and filter without the need to define a function or lambda just to call a method. Not everything revolves around OOP, even in Python.
– Evicatos
Nov 7 '...
Is using Random and OrderBy a good shuffle algorithm?
...basically giving a random (hopefully unique!) number to each element, then ordering the elements according to that number.
I prefer Durstenfield's variant of the Fisher-Yates shuffle which swaps elements.
Implementing a simple Shuffle extension method would basically consist of calling ToList or T...
Dynamic LINQ OrderBy on IEnumerable / IQueryable
...Examples for Dynamic LINQ that allows you to use a sql-like string (e.g. OrderBy("Name, Age DESC")) for ordering. Unfortunately, the method included only works on IQueryable<T> . Is there any way to get this functionality on IEnumerable<T> ?
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What is the best algorithm for overriding GetHashCode?
... /// <summary>
/// Gets a hashcode for a collection for that the order of items
/// does not matter.
/// So {1, 2, 3} and {3, 2, 1} will get same hash code.
/// </summary>
public static int GetHashCodeForOrderNoMatterCollection<T>(
IEnumerable<T> ...
SPAN vs DIV (inline-block)
...nces between Inline-Elements (e.g. span) and Block-Elements (e.g. div), in order to understand why "display: inline-block" is so useful.
Problem: inline elements (e.g. span, a, button, input etc.) take "margin" only horizontally (margin-left and margin-right) on, not vertically. Vertical spacing wor...
Visual Studio Project vs. Solution
...l be compiled into an executable program or web site, or else is needed in order to perform the compilation. A project also contains all the compiler settings and other configuration files that might be needed by various services or components that your program will communicate with.
You don't have ...
What are the basic rules and idioms for operator overloading?
Note: The answers were given in a specific order , but since many users sort answers according to votes, rather than the time they were given, here's an index of the answers in the order in which they make most sense:
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