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How to avoid explicit 'self' in Python?

...ereby break code. One extreme example: you can write a class without any knowledge of what base classes it might have, and always know whether you are accessing a member or not: class A(some_function()): def f(self): self.member = 42 self.method() That's the complete code! (some_funct...
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Scale image to fit a bounding box

...n it's container, and CSS can't do this. The reason is that CSS does not know what the page looks like. It sets rules beforehand, but only after that it is that the elements get rendered and you know exactly what sizes and ratios you're dealing with. The only way to detect that is with JavaScript. ...
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Explaining Python's '__enter__' and '__exit__'

... If you know what context managers are then you need nothing more to understand __enter__ and __exit__ magic methods. Lets see a very simple example. In this example I am opening myfile.txt with help of open function. The try/finally...
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data.frame rows to a list

...mp; } res.attr("names") = x.attr("row.names"); return res; } Now caompare with purrr: benchmark( purrr = by_row(x, function(v) list(v)[[1L]], .collate = "list")$.out, rcpp = df2list(x) ) Results: Benchmark summary: Time units : milliseconds expr n.eval min lw.qu median m...
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C programming in Visual Studio

...f your project and the Location you want it to install to, then click Ok. Now wait for the project to be created. Next under Solutions Explorer right click Source Files, select Add then New Item. You should see something like this: Rename Source.cpp to include a .c extension (Source.c for ex...
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Iterate through object properties

... I feel that I should mention, however, that Object.keys(obj) is now a much better solution for getting the keys of the object itself. Link to the Mozilla documentation: developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/… – Kyle Richter Apr ...
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How to find the kth largest element in an unsorted array of length n in O(n)?

...∑i=floor(n/2) to n T(i) <= cn + 2 (1/n) ∑i=floor(n/2) to n ai and now somehow we have to get the horrendous sum on the right of the plus sign to absorb the cn on the left. If we just bound it as 2(1/n) ∑i=n/2 to n an, we get roughly 2(1/n)(n/2)an = an. But this is too big - there's no r...
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Looping through a hash, or using an array in PowerShell

...not; because I, like most people, like my code to run as fast as possible. Now, your argument is changing to running jobs in parallel (potentially using multiple computers/servers) ... which of course is faster than running a job in series from a single thread. Cheers! – Vertig...
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Generate Java class from JSON?

...t. It's still in draft (not finalised) but it's close to completion and is now a viable tool specifying your structural rules I've recently started a new open source project specifically intended to solve your problem: jsonschema2pojo. The jsonschema2pojo tool takes a json schema document and gener...
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Simple explanation of MapReduce?

...rite it like this A = [7, 8, 9] sum = A.reduce( 0, (x, y) => x + y ) Now it's a little confusing why there are 2 arguments (0 and the function with x and y) passed. For a reduce function to be useful, it must be able to take 2 items, compute something and "reduce" that 2 items to just one sing...