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In Matlab, when is it optimal to use bsxfun?
... bsxfun with R2012b on my decently fast laptop.
For me, bsxfun is about 3 times faster than repmat. The difference becomes more pronounced if the arrays get larger
The jump in runtime of repmat happens around an array size of 1Mb, which could have something to do with the size of my processor ...
git remote prune – didn't show as many pruned branches as I expected
...es/origin/feature is a stale branch which should be removed.
Now you have 3 references, including refs/heads/feature, because git remote prune does not remove any refs/heads/* references.
It is possible to identify local branches, associated with remote tracking branches, by branch.<branch_nam...
Error handling principles for Node.js + Express.js applications?
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How can I change the color of my prompt in zsh (different from normal text)?
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Here's an example of how to set a red prompt:
PS1=$'\e[0;31m$ \e[0m'
The magic is the \e[0;31m (turn on red foreground) and \e[0m (turn off character attributes). These are called escape sequences. Different escape sequences give you different results, from absolute cursor positi...
Javascript replace with reference to matched group?
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What is the difference between libsqlite3.dylib and libsqlite3.0.dylib?
...s yet but one of the early steps from this tutorial is linking the SQLite3 framework. The tutorial calls for libsqlite3.0.dylib but I noticed another one libsqlite3.dylib. Is the latter just a symlink to the latest v3 library like the convention for package managers on UNIX or is there a differe...
Are parallel calls to send/recv on the same socket valid?
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ThreadStatic v.s. ThreadLocal: is generic better than attribute?
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How do I resize a Google Map with JavaScript after it has loaded?
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answered Apr 13 '09 at 7:36
SingleNegationEliminationSingleNegationElimination
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Counting the number of elements with the values of x in a vector
...an just use table():
> a <- table(numbers)
> a
numbers
4 5 23 34 43 54 56 65 67 324 435 453 456 567 657
2 1 2 2 1 1 2 1 2 1 3 1 1 1 1
Then you can subset it:
> a[names(a)==435]
435
3
Or convert it into a data.frame if you're more comfor...