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SQL Update with row_number()
...able and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator.
Instead, you could just have given the CTE a different name as well as added the target column to i...
Using two values for one switch case statement
...Days);
}
}
This is the output from the code:
Number of Days = 29
FALLTHROUGH:
Another point of interest is the break statement. Each break statement
terminates the enclosing switch statement. Control flow continues with
the first statement following the switch block. The break state...
Are foreign keys really necessary in a database design?
...grammer to manipulate data in the correct way. Suppose a programmer is actually doing this in the right manner already, then do we really need the concept of foreign keys?
...
Obstructed folders in Subversion
...olution can be to export the working copy (the entire checkout you have locally) to somewhere else.
If you are using tortoisesvn, you get the option to "export un-versioned files", but I think if doing it from the command line it only exports versioned files so you might have a bit of a laborious t...
How to set DOM element as the first child?
I have element E and I'm appending some elements to it. All of a sudden, I find out that the next element should be the first child of E. What's the trick, how to do it? Method unshift doesn't work because E is an object, not array.
...
JavaScript variable assignments from tuples
...
Javascript 1.7 added destructured assignment which allows you to do essentially what you are after.
function getTuple(){
return ["Bob", 24];
}
var [a, b] = getTuple();
// a === "bob" , b === 24 are both true
...
Apache redirect to another port
...//example.com in ProxyPass and ProxyPassReverse and leave it as /. Additionally, you need to leave the / at the end of example/ to where it is redirecting. Also, I had some trouble with http://example.com vs. http://www.example.com - only the www worked until I made the ServerName www.example.com, a...
How do I get the 'clear' command in Cygwin?
I installed Cygwin, choosing a fairly minimal set of packages.
10 Answers
10
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Add x and y labels to a pandas plot
...el", ylabel="y label").
Alternatively, the index x-axis label is automatically set to the Index name, if it has one. so df2.index.name = 'x label' would work too.
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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...