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Undefined method 'task' using Rake 0.9.0

I just updated Rake to the latest version ( 0.9.0.beta.4 ) and the rake command ends up with the following error message: ...
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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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How to use Regular Expressions (Regex) in Microsoft Excel both in-cell and loops

...ns: - Range. E.g. a-z matches an lower case letters from a to z E.g. 0-5 matches any number from 0 to 5 [] Match exactly one of the objects inside these brackets. E.g. [a] matches the letter a E.g. [abc] matches a single letter which can be a, b or c E.g. [a-z] matches any single lower cas...
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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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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 ...
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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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How can I scale the content of an iframe?

...ra and Safari if you change the CSS to: <style> #wrap { width: 600px; height: 390px; padding: 0; overflow: hidden; } #frame { width: 800px; height: 520px; border: 1px solid black; } #frame { -ms-zoom: 0.75; -moz-transform: scale(0.75); -moz-transform-origin...
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Dynamically select data frame columns using $ and a character value

...itten as `$`(df , V1) or indeed `$`(df , "V1") But... `$`(df , paste0("V1") ) ...for instance will never work, nor will anything else that must first be evaluated in the second argument. You may only pass a string which is never evaluated. Instead use [ (or [[ if you want to extract only...
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What's the simplest way to test whether a number is a power of 2 in C++?

... 190 (n & (n - 1)) == 0 is best. However, note that it will incorrectly return true for n=0, so i...
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Removing leading zeroes from a field in a SQL statement

...ve the leading zeroes from a particular field, which is a simple VARCHAR(10) field. So, for example, if the field contains '00001A', the SELECT statement needs to return the data as '1A'. ...