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Selecting multiple columns in a pandas dataframe
...1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of the ...
Difference between '..' (double-dot) and '…' (triple-dot) in range generation?
I've just started learning Ruby and Ruby on Rails and came across validation code that uses ranges:
5 Answers
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Strings as Primary Keys in SQL Database [closed]
I am not very familiar with databases and the theories behind how they work. Is it any slower from a performance standpoint (inserting/updating/querying) to use Strings for Primary Keys than integers?
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Git: can I suppress listing of 'modified content'/dirty submodule entries in status, diff, etc?
...module within the .gitmodules file.
Just today I encountered this problem and immediately wrote an article in my blog about it after finding a solution: How to ignore changes in git submodules
The gist of it:
Once you added a submodule there will be a file named .gitmodules in the root of your...
Could not open a connection to your authentication agent
...h-agent?
You might need to start ssh-agent before you run the ssh-add command:
eval `ssh-agent -s`
ssh-add
Note that this will start the agent for msysgit Bash on Windows. If you're using a different shell or operating system, you might need to use a variant of the command, such as those listed ...
How do I pass a class as a parameter in Java?
Is there any way to pass class as a parameter in Java and fire some methods from that class?
10 Answers
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Disable HttpClient logging
...egration test suite. The default logging for HttpClient is extremely noisy and I can't seem to turn it off. I've tried following the instructions here but none of them make any difference.
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Can you use Microsoft Entity Framework with Oracle? [closed]
...erly OraDirect .NET) now provides support for Entity Framework v4 Release Candidate devart.com/blogs/dotconnect/?p=2062
– Devart
Apr 2 '10 at 11:16
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Eclipse jump to closing brace
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Place the cursor next to an opening or closing brace and punch Ctrl + Shift + P to find the matching brace. If Eclipse can't find one you'll get a "No matching bracket found" message.
edit: as mentioned by Romaintaz below, you can also get Eclipse to auto-select all of the cod...
Type definition in object literal in TypeScript
...has methods as well as properties? Since the class doesn't get initialized and we only assign properties, calling a method on the class will cause a null exception. Basically, the object we create only 'acts' as the class because we assign its type, but it is not actually an instance of that class. ...