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Extract a dplyr tbl column as a vector
...on to make pulling out a column a bit nicer (easier to type, and easier to read):
pull <- function(x,y) {x[,if(is.name(substitute(y))) deparse(substitute(y)) else y, drop = FALSE][[1]]}
This lets you do either of these:
iris2 %>% pull('Species')
iris2 %>% pull(Species)
iris2 %>% pull...
Meaning of acronym SSO in the context of std::string
... a more realistic implementation, with the caveat that I've never actually read any implementation of SSO "in the wild".
Implementation details
At the minimum, a std::string needs to store the following information:
The size
The capacity
The location of the data
The size could be stored as a s...
Can I obtain method parameter name using Java reflection?
...If the class was compiled with debugging it can extract the information by reading the bytecode of the class.
Another way is for it to inject a private static member into the bytecode of the class after it is compiled, but before it is placed in a jar. It then uses reflection to extract this inform...
What are the best Haskell libraries to operationalize a program? [closed]
... 100.0% of total user, 0.0% of total elapsed
You can get this in machine-readable format too:
$ ./A +RTS -t --machine-readable
[("bytes allocated", "64952")
,("num_GCs", "1")
,("average_bytes_used", "43784")
,("max_bytes_used", "43784")
,("num_byte_usage_samples", "1")
,("peak_megabytes_al...
What is the maximum value for an int32?
... If you get the tattoo on your face, don't forget to reverse it so it reads correctly in the mirror. Otherwise you'll see 746,384,741,2 which is wrong and would be embarrassing.
– Larry S
Apr 21 '16 at 20:20
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JavaScript implementation of Gzip [closed]
...ok me some time but i found that in the JSXGraph library there is a way to read gzipped data.
Here is where I found the library: http://jsxgraph.uni-bayreuth.de/wp/2009/09/29/jsxcompressor-zlib-compressed-javascript-code/
There is even a standalone utility that can do that, JSXCompressor, and the c...
How do I kill all the processes in Mysql “show processlist”?
...mysql -u -p -e "show processlist;" | grep Sleep | awk '{print $1}' | while read LINE; do mysql -u -p -e "kill $LINE"; done
– user3770797
Nov 4 '17 at 20:55
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Adding a Method to an Existing Object Instance
I've read that it is possible to add a method to an existing object (i.e., not in the class definition) in Python.
16 Answ...
How to drop a database with Mongoose?
...creation script in Node.js and Mongoose.
How can I check if the database already exists, and if so, drop (delete) it using Mongoose?
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Visual Studio 2013 IntelliSense stops working for ASP.NET MVC5 Controllers
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Thanks, this worked for me too. If you read to the bottom try this before you remove all your extensions.
– Just another Steve
Jun 9 '14 at 20:17
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