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SQL Server IN vs. EXISTS Performance
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don't know why this excellent answer hasn't gotten any more attention. Understanding the index/structure for both sides could impact I agree. Well said.
– SheldonH
Apr 9 '15 at 20:57
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Easiest way to toggle 2 classes in jQuery
...etween on button click, what's a nice solution for that in jQuery? I still don't understand how toggleClass() works.
7 An...
how to make twitter bootstrap submenu to open on the left side?
I was trying to create twitter bootstrap submenu in dropdown menu, but I've got a problem: I have dropdown menu in the top right corner of the page and that menu has one more submenu. However, when submenu opens - it does not fit in the window and goes too much to the right, so that user can see onl...
Symbolic links and synced folders in Vagrant
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Virtualbox does not allow symlinks on shared folders for security reasons. To enable symlinks the following line needs to be added to the vm provider config block in the Vagrantfile:
config.vm.provider "virtualbox" do |v|
v.customi...
nodejs vs node on ubuntu 12.04
...ly create a symlink /usr/bin/node. Shortcut for bash compatible shells:
sudo ln -s `which nodejs` /usr/bin/node
Or if you use non-standard shells, just hardcode the path you find with which nodejs:
sudo ln -s /usr/bin/nodejs /usr/bin/node
Later edit
I found this explanation in the link you po...
Hide/Show Column in an HTML Table
... want to hide/show the corresponding column in the table. I would like to do this without attaching a class to every td in the table, is there a way to select an entire column using jquery? Below is an example of the HTML.
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Understanding FFT output
...to N. In your case it's easiest to simply ignore the outputs N/2 to N. You don't need them, they are just an artifact on how you calculate your FFT.
The frequency to fft-bin equation is (bin_id * freq/2) / (N/2) where freq is your sample-frequency (aka 32 Hz, and N is the size of your FFT). In your ...
How to print a int64_t type in C
... good as writing printf("%lld\n", t); See description : qnx.com/developers/docs/6.5.0/…
– Gaurav
Aug 14 '15 at 11:32
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Standardize data columns in R
... columns are numeric you can simply call the scale function on the data to do what you want.
dat <- data.frame(x = rnorm(10, 30, .2), y = runif(10, 3, 5))
scaled.dat <- scale(dat)
# check that we get mean of 0 and sd of 1
colMeans(scaled.dat) # faster version of apply(scaled.dat, 2, mean)
a...
Is Java Regex Thread Safe?
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Yes, from the Java API documentation for the Pattern class
Instances of this (Pattern) class are immutable and are safe for use by multiple concurrent threads. Instances of the Matcher class are not safe for such use.
If you are looking at perf...