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For every character in string
...ell, OK, it has no encoding, however given the ubiquity of utf8 now (especially on the web) and the fact that one might want a single consistent encoding throughout a pipeline or application, for the basis of this discussion my std::strings are all utf8 :p.
– Robinson
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Cluster analysis in R: determine the optimal number of clusters
...lidean",
method = "kmeans", min.nc=2, max.nc=15,
index = "alllong", alphaBeale = 0.1)
hist(nb$Best.nc[1,], breaks = max(na.omit(nb$Best.nc[1,])))
# Looks like 3 is the most frequently determined number of clusters
# and curiously, four clusters is not in the output at all!
If yo...
Javascript Shorthand for getElementById
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@patrick dw I like that. Especially with the wealth of valid variable names out there :)
– Fox Wilson
Jun 18 '11 at 20:56
4
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JPA: How to have one-to-many relation of the same Entity type
...em.persist(daughter);
em.getTransaction().commit();
}
In this case, all three entity instances must be persisted before transaction commit. If I fail to persist one of the entities in the graph of parent-child relationships, then an exception is thrown on commit(). On Eclipselink, this is a...
Easiest way to flip a boolean value?
...ses can be merged as they do the same thing.
– David Allan Finch
Mar 4 '09 at 15:16
1
Is default:...
Language Books/Tutorials for popular languages
... online tutorials to learn programming languages or platforms. These generally give you no more than a little taste of the language. To really learn a language, you need the equivalent of a "book", and in many cases, this means a real dead-tree book.
If you want to learn C, read K&R. If you ...
What is the difference between a deep copy and a shallow copy?
What is the difference between a deep copy and a shallow copy?
31 Answers
31
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Nokogiri installation fails -libxml2 is missing
I always worked my way around Nokogiri installation issues by following the documentation in the " Installing Nokogiri " tutorial.
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Force R not to use exponential notation (e.g. e+10)?
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This is a bit of a grey area. You need to recall that R will always invoke a print method, and these print methods listen to some options. Including 'scipen' -- a penalty for scientific display. From help(options):
‘scipen’: integer. A penalty to be applied wh...
PostgreSQL error: Fatal: role “username” does not exist
...I can't do anything with PostgreSQL: can't createdb , can't createuser ; all operations return the error message
15 Answe...