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How do you get the magnitude of a vector in Numpy?

...ray -- say x.norm() -- but oh well). import numpy as np x = np.array([1,2,3,4,5]) np.linalg.norm(x) You can also feed in an optional ord for the nth order norm you want. Say you wanted the 1-norm: np.linalg.norm(x,ord=1) And so on. ...
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All possible array initialization syntaxes

...s above, the first two could replace the string[] on the left with var (C# 3+), as the information on the right is enough to infer the proper type. The third line must be written as displayed, as array initialization syntax alone is not enough to satisfy the compiler's demands. The fourth could also...
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How to Correctly Use Lists in R?

...: Why do these two expressions not return the same result? x = list(1, 2, 3, 4); x2 = list(1:4) A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different ...
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Pandas get topmost n records within each group

... 3 Answers 3 Active ...
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Algorithm to return all combinations of k elements from n

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Jasmine.js comparing arrays

... 346 Just did the test and it works with toEqual please find my test: http://jsfiddle.net/7q9N7/3...
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Find which version of package is installed with pip

... As of pip 1.3, there is a pip show command. $ pip show Jinja2 --- Name: Jinja2 Version: 2.7.3 Location: /path/to/virtualenv/lib/python2.7/site-packages Requires: markupsafe In older versions, pip freeze and grep should do the job nice...
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Sorting a Python list by two fields

... BrechtDeMan 5,52433 gold badges2121 silver badges2424 bronze badges answered Mar 6 '11 at 19:38 mouadmouad ...
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How to access the ith column of a NumPy multidimensional array?

... >>> test[:,0] array([1, 3, 5]) Similarly, >>> test[1,:] array([3, 4]) lets you access rows. This is covered in Section 1.4 (Indexing) of the NumPy reference. This is quick, at least in my experience. It's certainly much quicker tha...
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How to get the Power of some Integer in Swift language?

...(radix), Double(power))) } // ... // Then you can do this... let i = 2 ^^ 3 // ... or println("2³ = \(2 ^^ 3)") // Prints 2³ = 8 I used two carets so you can still use the XOR operator. Update for Swift 3 In Swift 3 the "magic number" precedence is replaced by precedencegroups: precedencegro...