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dplyr: “Error in n(): function should not be called directly”
...blog and then run solution in detach("package:plyr", unload=TRUE)
Blog : https://www.analyticsvidhya.com/blog/2017/09/comparative-stock-analysis/
Master_Data_AutoCorrelations<-Master_Data_lags %>%
gather(key = "lag", value = "lag_value", -c(Stock,Date, Close)) %>%
mutate(lag = str_su...
ipython reads wrong python version
...
extremely relevant: http://conda.pydata.org/docs/troubleshooting.html#shell-command-location.
td;lr problems are encountered because of shell 'hashing' and path variables.
...
Why compile Python code?
...PHP and others.
Heres an interesting blog post explaining the differences http://julipedia.blogspot.com/2004/07/compiled-vs-interpreted-languages.html
And here's an entry that explains the Python compile process http://effbot.org/zone/python-compile.htm
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How does inheritance work for Attributes?
...eUploader: {
brandingHtml: "Powered by \u003ca href=\"https://imgur.com/\"\u003e\u003csvg class=\"svg-icon\" width=\"50\" height=\"18\" viewBox=\"0 0 50 18\" fill=\"none\" xmlns=\"http://www.w3.org/2000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 4...
Why use ICollection and not IEnumerable or List on many-many/one-many relationships?
... which methods you need access to. In general - IEnumerable<> (MSDN: http://msdn.microsoft.com/en-us/library/system.collections.ienumerable.aspx) for a list of objects that only needs to be iterated through, ICollection<> (MSDN: http://msdn.microsoft.com/en-us/library/92t2ye13.aspx) for ...
Logging uncaught exceptions in Python
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The method sys.excepthook will be invoked if an exception is uncaught: http://docs.python.org/library/sys.html#sys.excepthook
When an exception is raised and uncaught, the interpreter calls sys.excepthook with three arguments, the exception class, exception instance, and a traceback object. ...
Email address validation using ASP.NET MVC data type attributes
...ExpressionAttributeAdapter));
}
/// <summary>
/// from: http://stackoverflow.com/a/6893571/984463
/// </summary>
public EmailAnnotation()
: base(@"^[\w!#$%&'*+\-/=?\^_`{|}~]+(\.[\w!#$%&'*+\-/=?\^_`{|}~]+)*"
+ "@"
+ @"((([\-\w]+...
How to implement a queue with three stacks?
...iginal question
DETAILS
There are two implementations behind this link: http://www.eecs.usma.edu/webs/people/okasaki/jfp95/index.html
One of them is O(1) with three stacks BUT it uses lazy execution, which in practice creates extra intermediate data structures (closures).
Another of them is O(1...
Add custom messages in assert?
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BOOST_ASSERT_MSG(expre, msg)
http://www.boost.org/doc/libs/1_51_0/libs/utility/assert.html
You could either use that directly or copy Boost's code. Also note Boost assert is header only, so you could just grab that single file if you didn't want to inst...
difference between primary key and unique key
...ven by the author may not seem suitable, but try to get an overall idea.
http://tsqltips.blogspot.com/2012/06/difference-between-unique-key-and.html
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