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Summarizing multiple columns with dplyr? [duplicate]
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I mean, the behavior like in select would be great: summarize(df, a:c, d=paste(d, collaspe =',' ) . Just want to put more original columns in for reference
– biocyberman
Aug 8 '15 at 17:28
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Can you resolve an angularjs promise before you return it?
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I think this answer should be selected.
– Morteza Tourani
May 8 '16 at 20:13
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Unexpected value from nativeGetEnabledTags: 0
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Goto your Logcat
In the Saved Filters part on the left, click on the Edit selected logcat filter (If Saved Filters is not visible then click on Display Saved Filters View in the Logcat)
There, in the by Log Message field, enter ^(?!.*(nativeGetEnabledTags)).*$.
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How to get the date from jQuery UI datepicker
...tepicker_id').datepicker('getDate');
if (jsDate !== null) { // if any date selected in datepicker
jsDate instanceof Date; // -> true
jsDate.getDate();
jsDate.getMonth();
jsDate.getFullYear();
}
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How do I convert an integer to string as part of a PostgreSQL query?
...o 15 digits, you'll meed to cast to an 64 bit (8-byte) integer. Try this:
SELECT * FROM table
WHERE myint = mytext::int8
The :: cast operator is historical but convenient. Postgres also conforms to the SQL standard syntax
myint = cast ( mytext as int8)
If you have literal text you want to c...
Why does ReSharper want to use 'var' for everything?
...Dictionary<int,bool>>>> q = from t in d where t.Key == null select t; // OMG!
//vs.
var q = from t in d where t.Key == null select t;
// I simply want the first string, so the last version seems fine.
q.First().Key;
You must use var when there's an anonymous ty...
Node.js Best Practice Exception Handling
...any different sources on this topic including code example and quotes from selected blog posts. The complete list of best practices can be found here
Best practices of Node.JS error handling
Number1: Use promises for async error handling
TL;DR: Handling async errors in callback style is proba...
What is pseudopolynomial time? How does it differ from polynomial time?
...mon intuition for polynomial time is "time O(nk) for some k." For example, selection sort runs in time O(n2), which is polynomial time, while brute-force solving TSP takes time O(n · n!), which isn't polynomial time.
These runtimes all refer to some variable n that tracks the size of the input. Fo...
USB Debugging option greyed out
...of this post.
When you connect your phone to your PC, using the USB cable, select the mode as PC Software.
Now you should be able to enable USB Debugging.
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How to set breakpoints in inline Javascript in Google Chrome?
...e directory tree underneath it (with the up and down arrow in it), you can select the file you want to debug. You can get out of an error by pressing resume on the right-hand side of the same tab.
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