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C# Convert List to Dictionary
...ts you pick the key, the second one picks the value.
You can play with it and make values differ from the keys, like this:
var res = list.ToDictionary(x => x, x => string.Format("Val: {0}", x));
If your list contains duplicates, add Distinct() like this:
var res = list.Distinct().ToDictio...
How to Select Every Row Where Column Value is NOT Distinct
... thing that is incorrect with your query is that you are grouping by email and name, that forms a group of each unique set of email and name combined together and hence
aaron and aaron@gmail.com
christy and aaron@gmail.com
john and aaron@gmail.com
are treated as 3 different groups rather all bel...
Strings in a DataFrame, but dtype is object
Why does Pandas tell me that I have objects, although every item in the selected column is a string — even after explicit conversion.
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How does libuv compare to Boost/ASIO?
...a thread abstraction, as Boost.Thread already provides one.
On the other hand, libuv is a C library designed to be the platform layer for Node.js. It provides an abstraction for IOCP on Windows, kqueue on macOS, and epoll on Linux. Additionally, it looks as though its scope has increased slightly...
What is the difference between SQL Server 2012 Express versions?
... this page http://www.microsoft.com/en-us/download/details.aspx?id=29062 and I am a bit confused about the different versions here.
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Temporarily disable Eclipse plugin
...havior. These will be listed in the preferences, under General → Startup and Shutdown. If the plugin provides view, you will need to close those views (in all perspectives) for this to work.
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Making macOS Installer Packages which are Developer ID ready
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Our example project has two build targets: HelloWorld.app and Helper.app. We make a component package for each and combine them into a product archive.
A component package contains payload to be installed by the OS X Installer. Although a component
package can be installed on ...
How to use chrome web inspector to view hover code
... hover code for a button? You will have to hover the mouse over the button and thus cannot use it (mouse) in the inspector. Are there any shortcuts or other ways to accomplish this in the inspector?
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Extract elements of list at odd positions
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Solution
Yes, you can:
l = L[1::2]
And this is all. The result will contain the elements placed on the following positions (0-based, so first element is at position 0, second at 1 etc.):
1, 3, 5
so the result (actual numbers) will be:
2, 4, 6
Explanation...
What are the performance characteristics of sqlite with very large database files? [closed]
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So I did some tests with sqlite for very large files, and came to some conclusions (at least for my specific application).
The tests involve a single sqlite file with either a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices.
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