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What is the difference between memoization and dynamic programming?
...he computations of the subproblems overlap.
Dynamic programming is typically implemented using tabulation, but can also be implemented using memoization. So as you can see, neither one is a "subset" of the other.
A reasonable follow-up question is: What is the difference between tabulation (th...
Should I use scipy.pi, numpy.pi, or math.pi?
...gt;> math.pi == np.pi == scipy.pi
True
So it doesn't matter, they are all the same value.
The only reason all three modules provide a pi value is so if you are using just one of the three modules, you can conveniently have access to pi without having to import another module. They're not provi...
What is Virtual DOM?
Recently, I looked at Facebook's React framework. It uses a concept called "the Virtual DOM," which I didn't really understand.
...
What is Normalisation (or Normalization)?
...
Normalization is basically to design a database schema such that duplicate and redundant data is avoided. If some piece of data is duplicated several places in the database, there is the risk that it is updated in one place but not the other, lead...
iOS 7.0 No code signing identities found
...ofile
Create New or Edit existing Provisioning profile.
Download and install.
For BundleIdentifier.
com.yourcompanyName.Something (Put same as in AppId)
CodeSigningIdentity.
Select The Provisioning profile which you created.
...
Table overflowing outside of div
...
This forces all of the columns to be the same width... not very useful
– Serj Sagan
Jul 9 '13 at 1:36
11
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Maven - How to compile tests without running them ?
...without running them ? I want to use the IDE to run specific tests and not all of them.
7 Answers
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Where do I put image files, css, js, etc. in Codeigniter?
....php:
function asset_url(){
return base_url().'assets/';
}
I will usually keep common routines similar to this in the same file and autoload it with codeigniter's autoload configuration.
Note: autoload URL helper for base_url() access.
application/config/autoload.php:
$autoload['helper...
Recursive Lock (Mutex) vs Non-Recursive Lock (Mutex)
POSIX allows mutexes to be recursive. That means the same thread can lock the same mutex twice and won't deadlock. Of course it also needs to unlock it twice, otherwise no other thread can obtain the mutex. Not all systems supporting pthreads also support recursive mutexes, but if they want to be P...
OO Design in Rails: Where to put stuff
I'm really enjoying Rails (even though I'm generally RESTless), and I enjoy Ruby being very OO. Still, the tendency to make huge ActiveRecord subclasses and huge controllers is quite natural (even if you do use a controller per resource). If you were to create deeper object worlds, where would you p...