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Split delimited strings in a column and insert as new rows [duplicate]
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Now you can use tidyr 0.5.0's separate_rows is in place of strsplit + unnest.
For example:
library(tidyr)
(df <- read.table(textConnection("1|a,b,c\n2|a,c\n3|b,d\n4|e,f"), header = F, sep = "|", stringsAsFactors = F))
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Differences between Emacs and Vim
...ftp client, tetris, ... whatnot in one package (emacs) made some sense ... nowadays, it doesn't anymore.
Both are however a topic of religious discussions among the programmer and superuser community users, and in that respect, both are excellent for starting flame wars if put in contact (in the sa...
Is there a performance difference between i++ and ++i in C?
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I know this question is about C, but I'd be interested to know if browsers can do this optimization for javascript.
– TM.
Aug 12 '09 at 21:58
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Generating an Excel file in ASP.NET [closed]
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Cons:
Limited compatibility outside Excel 2007 (shouldn't be a problem nowadays)
Complicated unless you're using a third party component
SpreadSheetML (open format XML)
Pros:
Simple compared to native Excel formats
Supports most Excel features: formating, styles, formulas, multiple sheets ...
Must Dependency Injection come at the expense of Encapsulation?
...r to have its dependency fulfilled. Some provider of the dependency must know both that the object in question requires a Foo, and the provider has to have a way of providing the Foo to the object.
Classically this latter case is handled as you say, through constructor arguments or setter methods....
map vs. hash_map in C++
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An unordered_map should give slightly better performance for accessing known elements of the collection, but a map will have additional useful characteristics (e.g. it is stored in sorted order, which allows traversal from start to finish). unordered_map will be faster on insert and delete than ...
Android: AsyncTask vs Service
...syncTask and Loaders but nothing about Services ? Are Services just not known very well or are they deprecated or have some bad attributes or something? What are the differences?
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When to use inline function and when not to use it?
I know that inline is a hint or request to compiler and its used to avoid function call overheads.
14 Answers
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Is Ruby pass by reference or by value?
... Ruby is pass-by-value. No ifs. No buts. No exceptions. If you want to know whether Ruby (or any other language) is pass-by-reference or pass-by-value, just try it out: def foo(bar) bar = 'reference' end; baz = 'value'; foo(baz); puts "Ruby is pass-by-#{baz}".
– Jörg W Mitt...
API Keys vs HTTP Authentication vs OAuth in a RESTful API
... @TomDoe Hi Tom - Yes that makes sense. You probably want to use OAuth2 now. If your server is in Python (Django or Flask) take a look at github.com/omab/python-social-auth
– Sid
Aug 18 '15 at 19:43
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