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Regular expression for floating point numbers

... TL;DR Use [.] instead of \. and [0-9] instead of \d to avoid escaping issues in some languages (like Java). Thanks to the nameless one for originally recognizing this. One relatively simple pattern for matching a floating point number is [+-]?([0-9]*[.])...
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How to extract the decision rules from scikit-learn decision-tree?

... print "{}return {}".format(indent, tree_.value[node]) recurse(0, 1) This prints out a valid Python function. Here's an example output for a tree that is trying to return its input, a number between 0 and 10. def tree(f0): if f0 <= 6.0: if f0 <= 1.5: return [[ 0.]] ...
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How do you rotate a two dimensional array?

...ay you have a 4x4 two dimensional array, write a function that rotates it 90 degrees. Raymond links to a solution in pseudo code, but I'd like to see some real world stuff. ...
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Convert RGB to RGBA over white

...ha value. Example: 152 converts to an alpha value of (255 - 152) / 255 ~ 0.404 152 scales using (152 - 152) / 0.404 = 0 177 scales using (177 - 152) / 0.404 ~ 62 202 scales using (202 - 152) / 0.404 ~ 123 So, rgb(152, 177, 202) displays as rgba(0, 62, 123, .404). I have verified in Photoshop t...
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What is the colon operator in Ruby?

... 250 :foo is a symbol named "foo". Symbols have the distinct feature that any two symbols named the s...
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What are the mathematical/computational principles behind this game?

... 150 Finite Projective Geometries The axioms of projective (plane) geometry are slightly different ...
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JS Client-Side Exif Orientation: Rotate and Mirror JPEG Images

...erver or anything. – igneosaur May 20 '16 at 8:28 3 @igneosaur: you can send base64 encoded data ...
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How do I set a background-color for the width of text, not the width of the entire element, using CS

... I want is for the green background to be just behind the text, not to be 100% of the page width. Here is my current code: ...
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How do I replace NA values with zeros in an R dataframe?

...nt in @gsk3 answer. A simple example: > m <- matrix(sample(c(NA, 1:10), 100, replace = TRUE), 10) > d <- as.data.frame(m) V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 1 4 3 NA 3 7 6 6 10 6 5 2 9 8 9 5 10 NA 2 1 7 2 3 1 1 6 3 6 NA 1 4 1 6 4 NA 4 NA 7 10 2 NA 4 1...
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What are the advantages of using nullptr?

... handle nullptr argument!!! 1. In C++, NULL is defined as #define NULL 0, so it is basically int, that is why f(int) is called. share | improve this answer | follow ...