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How is this fibonacci-function memoized?
...mechanism in Haskell is by-need: when a value is needed, it is calculated, and kept ready in case it is asked for again. If we define some list, xs=[0..] and later ask for its 100th element, xs!!99, the 100th slot in the list gets "fleshed out", holding the number 99 now, ready for next access.
Th...
How do I return multiple values from a function? [closed]
...ing library got the NamedTuple class to make named tuples easier to create and more powerful. Inheriting from typing.NamedTuple lets you use docstrings, default values, and type annotations.
Example (From the docs):
class Employee(NamedTuple): # inherit from typing.NamedTuple
name: str
id...
What is the difference between “JPG” / “JPEG” / “PNG” / “BMP” / “GIF” / “TIFF” Image?
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Yes. They are different file formats (and their file extensions).
Wikipedia entries for each of the formats will give you quite a bit of information:
JPEG (or JPG, for the file extension; Joint Photographic Experts Group)
PNG (Portable Network Graphics)
BMP (B...
How to request Administrator access inside a batch file
....bat file. The desired behavior is that when they right-click on the file and say Open, they will get one of those UAC dialogs that makes the screen go dark and forces them to answer whether they want to give the application permission to run as administrator. Instead, they are just seeing "Access...
Unpacking, extended unpacking and nested extended unpacking
...lain with a few examples. Since you're talking about evaluating these "by hand," I'll suggest some simple substitution rules. Basically, you might find it easier to understand an expression if all the iterables are formatted in the same way.
For the purposes of unpacking only, the following substit...
How are the points in CSS specificity calculated
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Pekka's answer is practically correct, and probably the best way to think about the issue.
However, as many have already pointed out, the W3C CSS recommendation states that "Concatenating the three numbers a-b-c (in a number system with a large base) gives the sp...
Why would you use an ivar?
...is question asked the other way, such as Must every ivar be a property? (and I like bbum's answer to this Q).
7 Answers
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WebSockets protocol vs HTTP
There are many blogs and discussions about websocket and HTTP, and many developers and sites strongly advocate websockets, but i still can not understand why.
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SLF4J: Failed to load class “org.slf4j.impl.StaticLoggerBinder”
My application is to be deployed on both tcServer and WebSphere 6.1. This application uses ehCache and so requires slf4j as a dependency.
As a result I've added the slf4j-api.jar (1.6) jar to my war file bundle.
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How to check BLAS/LAPACK linkage in NumPy and SciPy?
I am builing my numpy/scipy environment based on blas and lapack more or less based on this walk through.
5 Answers
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