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Geometric Mean: is there a built-in?
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Here is a vectorized, zero- and NA-tolerant function for calculating geometric mean in R. The verbose mean calculation involving length(x) is necessary for the cases where x contains non-positive values.
gm_mean = function(x, na.rm=TRUE){
exp(sum(log...
Is there a benefit to defining a class inside another class in Python?
...Essentially, I have two classes that I'm modeling. A DownloadManager class and a DownloadThread class. The obvious OOP concept here is composition. However, composition doesn't necessarily mean nesting, right?
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How do I parse an ISO 8601-formatted date?
...atetime strings like the one in the question, but also other ISO 8601 date and time strings that don't comply with RFC 3339 (such as ones with no UTC offset, or ones that represent only a date).
>>> import dateutil.parser
>>> dateutil.parser.isoparse('2008-09-03T20:56:35.450686Z'...
Find and replace with sed in directory and sub directories
I run this command to find and replace all occurrences of 'apple' with 'orange' in all files in root of my site:
7 Answers
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How to attach debugger to iOS app after launch?
I have an issue I am troubleshooting which occurs very infrequently and doesn't seem to happen when I have things running under Xcode.
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SSL Error When installing rubygems, Unable to pull data from 'https://rubygems.org/
...ws note
The Ruby Installer builds for windows are prepared by Luis Lavena and the path to certificates will be showing something like C:/Users/Luis/... check https://github.com/oneclick/rubyinstaller/issues/249 for more details and this answer https://stackoverflow.com/a/27298259/497756 for fix.
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HTML5 placeholder css padding
I've seen this post already and tried everything I could to change the padding for my placeholder but alas, it seems it just doesn't want to cooperate.
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How do I pass a unique_ptr argument to a constructor or a function?
I'm new to move semantics in C++11 and I don't know very well how to handle unique_ptr parameters in constructors or functions. Consider this class referencing itself:
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How to check if all elements of a list matches a condition?
...ne this with a generator expression to produce the result you want cleanly and efficiently. For example:
>>> items = [[1, 2, 0], [1, 2, 0], [1, 2, 0]]
>>> all(flag == 0 for (_, _, flag) in items)
True
>>> items = [[1, 2, 0], [1, 2, 1], [1, 2, 0]]
>>> all(flag == ...
What are POD types in C++?
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POD stands for Plain Old Data - that is, a class (whether defined with the keyword struct or the keyword class) without constructors, destructors and virtual members functions. Wikipedia's article on POD goes into a bit more detail...