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What is dynamic programming? [closed]
...ith dynamic programming, you store your results in some sort of table generally. When you need the answer to a problem, you reference the table and see if you already know what it is. If not, you use the data in your table to give yourself a stepping stone towards the answer.
The Cormen Algorithms ...
How to suppress scientific notation when printing float values?
...cify how many digit after the . you wish to display, this depends on how small is the floating number). See this example:
>>> a = -7.1855143557448603e-17
>>> '{:f}'.format(a)
'-0.000000'
as shown above, default is 6 digits! This is not helpful for our case example, so instead we...
What is the difference between the kernel space and the user space?
...
The really simplified answer is that the kernel runs in kernel space, and normal programs run in user space. User space is basically a form of sand-boxing -- it restricts user programs so they can't mess with memory (and other reso...
A cron job for rails: best practices?
...
I'm using the rake approach (as supported by heroku)
With a file called lib/tasks/cron.rake ..
task :cron => :environment do
puts "Pulling new requests..."
EdiListener.process_new_messages
puts "done."
end
To execute from the command line, this is just "rake cron". This command ...
How to properly assert that an exception gets raised in pytest?
...
There are two ways to handle these kind of cases in pytest:
Using pytest.raises function
Using pytest.mark.xfail decorator
As the documentation says:
Using pytest.raises is likely to be better for cases where you are testing exceptions your ow...
Counting the Number of keywords in a dictionary in python
... the len() function.
> a = {'foo':42, 'bar':69}
> len(a)
2
To get all the distinct words (i.e. the keys), use the .keys() method.
> list(a.keys())
['foo', 'bar']
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How to get a JavaScript object's class?
...
ES5 has aditionally Object.getPrototypeOf()
– Christoph
Aug 8 '09 at 18:52
29
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How to fix: “UnicodeDecodeError: 'ascii' codec can't decode byte”
...e source it's difficult to know the root cause, so I'll have to speak generally.
UnicodeDecodeError: 'ascii' codec can't decode byte generally happens when you try to convert a Python 2.x str that contains non-ASCII to a Unicode string without specifying the encoding of the original string.
In bri...
Iterate keys in a C++ map
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If you really need to hide the value that the "real" iterator returns (for example because you want to use your key-iterator with standard algorithms, so that they operate on the keys instead of the pairs), then take a look at Boost's...
How to obtain Signing certificate fingerprint (SHA1) for OAuth 2.0 on Android?
...p following the steps in https://developers.google.com/console/help/#installed_applications which leads me to follow
http://developer.android.com/tools/publishing/app-signing.html .
...