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What is “entropy and information gain”?
I am reading this book ( NLTK ) and it is confusing. Entropy is defined as :
7 Answers
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How do the PHP equality (== double equals) and identity (=== triple equals) comparison operators dif
What is the difference between == and === in PHP?
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Speed up the loop operation in R
... over a data.frame object. It simply adds a new column to a data.frame and accumulates something. (simple operation). The data.frame has roughly 850K rows. My PC is still working (about 10h now) and I have no idea about the runtime.
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What does the “yield” keyword do?
What is the use of the yield keyword in Python, and what does it do?
42 Answers
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Floating point vs integer calculations on modern hardware
I am doing some performance critical work in C++, and we are currently using integer calculations for problems that are inherently floating point because "its faster". This causes a whole lot of annoying problems and adds a lot of annoying code.
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What are the key differences between Apache Thrift, Google Protocol Buffers, MessagePack, ASN.1 and
All of these provide binary serialization, RPC frameworks and IDL. I'm interested in key differences between them and characteristics (performance, ease of use, programming languages support).
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What is recursion and when should I use it?
One of the topics that seems to come up regularly on mailing lists and online discussions is the merits (or lack thereof) of doing a Computer Science Degree. An argument that seems to come up time and again for the negative party is that they have been coding for some number of years and they have n...
Python assigning multiple variables to same value? list behavior
...he behavior, I expect to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
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What's the difference between eval, exec, and compile?
I've been looking at dynamic evaluation of Python code, and come across the eval() and compile() functions, and the exec statement.
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What is a plain English explanation of “Big O” notation?
I'd prefer as little formal definition as possible and simple mathematics.
41 Answers
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