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Automatically expanding an R factor into a collection of 1/0 indicator variables for every factor le
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And if you want to convert all factor columns, you can use: model.matrix(~., data=iris)[,-1]
– user890739
Jan 5 '16 at 0:32
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Remove portion of a string after a certain character
...ich I think addresses everything below and also explains ways to deal with all kinds of things like case insensitive, multiple occurrences, and regular expressions. If anyone wants to do anything more flexible or doesn't have control over the input coming in it's probably worth checking out.
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SSH configuration: override the default username [closed]
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Create a file called config inside ~/.ssh. Inside the file you can add:
Host *
User buck
Or add
Host example
HostName example.net
User buck
The second example will set a username and is hostname specific, while the first e...
Getting the IP address of the current machine using Java
... has the following effect: it sets the destination for Send/Recv, discards all packets from other addresses, and - which is what we use - transfers the socket into "connected" state, settings its appropriate fields. This includes checking the existence of the route to the destination according to th...
When is it acceptable to call GC.Collect?
The general advise is that you should not call GC.Collect from your code, but what are the exceptions to this rule?
24 An...
Remove tracking branches no longer on remote
Is there a simple way to delete all tracking branches whose remote equivalent no longer exists?
34 Answers
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Detecting superfluous #includes in C/C++?
I often find that the headers section of a file get larger and larger all the time but it never gets smaller. Throughout the life of a source file classes may have moved and been refactored and it's very possible that there are quite a few #includes that don't need to be there and anymore. Leaving...
How are ssl certificates verified?
...private key of a trusted certificate authority.
Your web browser comes installed with the public keys of all of the major certificate authorities. It uses this public key to verify that the web server's certificate was indeed signed by the trusted certificate authority.
The certificate contains the...
How can I find where Python is installed on Windows?
I want to find out my Python installation path on Windows. For example:
19 Answers
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Why use finally in C#?
Whatever is inside finally blocks is executed (almost) always, so what's the difference between enclosing code into it or leaving it unclosed?
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