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How do I pass JavaScript variables to PHP?
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edited Aug 2 '19 at 1:05
Peter Mortensen
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Cluster analysis in R: determine the optimal number of clusters
...1)*i^2))))
plot(d)
One. Look for a bend or elbow in the sum of squared error (SSE) scree plot. See http://www.statmethods.net/advstats/cluster.html & http://www.mattpeeples.net/kmeans.html for more. The location of the elbow in the resulting plot suggests a suitable number of clusters for th...
Measuring elapsed time with the Time module
...esolution.
Use of these can further eliminate rounding and floating-point errors, especially if you're measuring very short periods, or your application (or Windows machine) is long-running.
Resolution starts breaking down on perf_counter() after around 100 days. So for example after a year of upt...
What is copy-on-write?
...enance of instant snapshot on database servers like Microsoft SQL Server 2005. Instant snapshots preserve a static view of a database by storing a pre-modification copy of data when underlaying data are updated. Instant snapshots are used for testing uses or moment-dependent reports and should not b...
How do you create different variable names while in a loop? [duplicate]
...st that don't yet exist (you'll get a "list assignment index out of range" error). You may want to use string.append("Hello") instead.
– Greg Hewgill
May 31 '11 at 1:10
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“Large data” work flows using pandas
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– Yaroslav Nikitenko
Apr 7 '19 at 6:05
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Block Comments in Clojure
... arbitrary text. For example, (comment "print("/foo")") will die with the error Invalid token: /foo.
– John Wiseman
May 12 '17 at 20:50
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C++ templates that accept only certain types
...T*> {
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// All other types are invalid, and will cause linker error messages.
[Minor EDIT 6/12/2013: Using a declared-but-not-defined template will result in linker, not compiler, error messages.]
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Writing string to a file on a new line every time
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as suggested by another answer, but why using string concatenation (slow, error-prone) when you can call file.write twice:
file.write(your_string)
file.write("\n")
note that writes are buffered so it amounts to the same thing.
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How to forward declare a template class in namespace std?
and used that function in my main. I get errors. Of course, I know that there are more template params for std::list (allocator I think). But, that is beside the point. Do I have to know the full template declaration of a template class to be able to forward declare it?
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