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Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
cannot download, $GOPATH not set
...ults to $HOME/go, but you may still find this useful if you want to understand the GOPATH layout, customize it, etc.]
The official Go site discusses GOPATH and how to lay out a workspace directory.
export GOPATH="$HOME/your-workspace-dir/" -- run it in your shell, then add it to ~/.bashrc or equiv...
What is the most robust way to force a UIView to redraw?
... building my view hierarchy. the subclass in question gets passed the data and it's drawRect method now has everything it needs to render.
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How can I default a parameter to Guid.Empty in C#?
...sage not tell me this, the complier could check for the case of Guid.Empty and give a more helpfull message.
– Ian Ringrose
Feb 25 '11 at 13:57
4
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Oracle TNS names not showing when adding new connection to SQL Developer
...RACLE\ORACLE_HOME
To see which one SQL Developer is using, issue the command show tns in the worksheet
If your tnsnames.ora file is not getting recognized, use the following procedure:
Define an environmental variable called TNS_ADMIN to point to the folder that contains your tnsnames.ora file....
Generate a random point within a circle (uniformly)
I need to generate a uniformly random point within a circle of radius R .
21 Answers
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Is there any way to close a StreamWriter without closing its BaseStream?
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@Yepeekai: "if I pass a stream to a sub method and that sub method create the StreamWriter, it will be disposed at the end of the execution of that sub method" No, that's simply not true. It will only be disposed if something calls Dispose on it. The method ending doesn't...
Rspec: “array.should == another_array” but without concern for order
I often want to compare arrays and make sure that they contain the same elements, in any order. Is there a concise way to do this in RSpec?
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What would cause an algorithm to have O(log n) complexity?
My knowledge of big-O is limited, and when log terms show up in the equation it throws me off even more.
6 Answers
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When is JavaScript synchronous?
...ns). Is there a good reference anywhere about when it will be synchronous and when it will be asynchronous? Does jQuery affect this at all?
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