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Shading a kernel density plot between two points.

...ently use kernel density plots to illustrate distributions. These are easy and fast to create in R like so: 5 Answers ...
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Best way of returning a random boolean value

... A declarative snippet using Array#sample: random_boolean = [true, false].sample share | improve this answer | follow | ...
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Why is reading lines from stdin much slower in C++ than Python?

I wanted to compare reading lines of string input from stdin using Python and C++ and was shocked to see my C++ code run an order of magnitude slower than the equivalent Python code. Since my C++ is rusty and I'm not yet an expert Pythonista, please tell me if I'm doing something wrong or if I'm mis...
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Selecting data frame rows based on partial string match in a column

...a data.table (but also remember that subsetting approaches for data.frames and data.tables are not identical): library(data.table) mtcars[rownames(mtcars) %like% "Merc", ] iris[iris$Species %like% "osa", ] If that is what you had, then perhaps you had just mixed up row and column positions for su...
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Are there any O(1/n) algorithms?

...put size for which the algorithm is not supposed to execute any operation. And therefore I would think that O(1/n) time complexity is indeed impossible to achieve. – Roland Ewald May 25 '09 at 14:10 ...
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Convert RGBA PNG to RGB with PIL

...com/mC4Wgqzv Thanks! Two things about your post though: The png.load() command seems to be unnecessary, and line 4 should be background = Image.new("RGB", png.size, (255, 255, 255)). – Danilo Bargen Feb 27 '12 at 14:39 ...
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How to format a float in javascript?

.....or just use toFixed, as proposed by Tim Büthe. Forgot that one, thanks (and an upvote) for reminder :) share | improve this answer | follow | ...
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Fill SVG path element with a background-image

...100" height="100" /> </pattern> </defs> Adjust the width and height according to your image, then reference it from the path like this: <path d="M5,50 l0,100 l100,0 l0,-100 l-100,0 M215,100 a50,50 0 1 1 -100,0 50,50 0 1 1 100,0 M265,50 ...
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LINQ with groupby and count

...g>, where each Grouping itself exposes the Key used to create the group and also is an IEnumerable<T> of whatever items are in your original data set. You just have to call Count() on that Grouping to get the subtotal. foreach(var line in data.GroupBy(info => info.metric) ...
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What's the best way to get the last element of an array without deleting it?

... many different options. To be able to choose from them I needed to understand their behavior and performance. In this answer I will share my findings with you, benchmarked against PHP versions 5.6.38, 7.2.10 and 7.3.0RC1 (expected Dec 13 2018). The options (<<option code>>s) I will tes...