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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...
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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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...
Hide/Show Column in an HTML Table
...
I would like to do this without attaching a class to every td
Personally, I would go with the the class-on-each-td/th/col approach. Then you can switch columns on and off using a single write to className on the container, assuming style rules like:
table.hide1 .col1 { display: none; }
table...
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...
Why is sizeof considered an operator?
.... Indeed, that's kind of the point of sizeof.
A function would differ on all those points. There are probably other differences between a function and a unary operator, but I think that's enough to show why sizeof could not be a function even if there was a reason to want it to be.
...
Get the device width in javascript
...th property.
Sometimes it's also useful to use window.innerWidth (not typically found on mobile devices) instead of screen width when dealing with desktop browsers where the window size is often less than the device screen size.
Typically, when dealing with mobile devices AND desktop browsers I use...
Reading a resource file from within jar
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I had this problem before and I made fallback way for loading. Basically first way work within .jar file and second way works within eclipse or other IDE.
public class MyClass {
public static InputStream accessFile() {
String resource = "my-file-loc...
How can you strip non-ASCII characters from a string? (in C#)
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For those of us RegEx'd challenged, would you mind writing out in plain english your RegEx pattern. In other words, "the ^ does this", etc...
– Metro Smurf
Sep 23 '08 at 22:45
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