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What are the differences between vector and list data types in R?
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Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY name ORDER BY id DESC) AS rn
FROM messages AS m...
python assert with and without parenthesis
...through IDLE. Because assert is a keyword and not a function, you are actually passing in a tuple as the first argument and leaving off the second argument.
Recall that non-empty tuples evaluate to True, and since the assertion message is optional, you've essentially called assert True when you wr...
How do I convert a Vector of bytes (u8) to a string
...("result: {}", s);
}
The conversion is in-place, and does not require an allocation. You can create a String from the string slice if necessary by calling .to_owned() on the string slice (other options are available).
The library reference for the conversion function:
std::str::from_utf8
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Add line break to 'git commit -m' from the command line
... rsy$ bash --version GNU bash, version 3.2.53(1)-release (x86_64-apple-darwin13) Copyright (C) 2007 Free Software Foundation, Inc. The output of that command is, as expected, shown in two different lines!
– ccoutinho
Jun 2 '15 at 21:49
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possible EventEmitter memory leak detected
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I am using process.on('uncaughtException', callback);
– Riz
Mar 19 '12 at 10:51
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A route named “x” is already in the route collection. Route names must be unique. Exception with ASP
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To fix this problem I had to go into the bin folder on my project, delete all DLL files and then rebuild and this fixed the problem.
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(grep) Regex to match non-ASCII characters?
...y with lots of files. Some of them have non-ASCII characters, but they are all valid UTF-8 . One program has a bug that prevents it working with non-ASCII filenames, and I have to find out how many are affected. I was going to do this with find and then do a grep to print the non-ASCII characte...
Java's Interface and Haskell's type class: differences and similarities?
...d say that an interface is kind of like a type class SomeInterface t where all of the values have the type t -> whatever (where whatever does not contain t). This is because with the kind of inheritance relationship in Java and similar languages, the method called depends on the type of object th...
Asp.NET Web API - 405 - HTTP verb used to access this page is not allowed - how to set handler mappi
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Common cause for this error is WebDAV. Make sure you uninstall it.
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