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Pass a data.frame column name to a function
...e more about tidyeval here.
library(rlang)
library(tidyverse)
set.seed(123)
df <- data.frame(B = rnorm(10), D = rnorm(10))
Use column names as strings
fun3 <- function(x, ...) {
# capture strings and create variables
dots <- ensyms(...)
# unquote to evaluate inside dplyr verbs
...
What are the differences between a pointer variable and a reference variable in C++?
...e of that object becomes the lifetime of the reference.
std::string s1 = "123";
std::string s2 = "456";
std::string s3_copy = s1 + s2;
const std::string& s3_reference = s1 + s2;
In this example s3_copy copies the temporary object that is a result of the concatenation. Whereas s3_reference in...
What is Type-safe?
...
On the down side, with type safe languages, when you have a string like "123" and you want to operate on it like an int, you have to write more code to convert the string to an int, or when you have an
Understanding offsetWidth, clientWidth, scrollWidth and -Height, respectively
...nswered Jan 11 '14 at 15:26
user123444555621user123444555621
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Git log to get commits only for a specific branch
...en there is no default & no pattern
| | defined.
| |
| * commit 80c123b9dbd1c1b3301ec1270adc6c07824aeb5c
| | Author: Mark Story <mark@mark-story.com>
| | Date: Sun Aug 28 22:35:20 2016 -0400
| |
| | Do fewer allocations for simple default values.
| |
| | Don't allocate arrays...
RESTful Alternatives to DELETE Request Body
...ngs. The query string is part of the URI. Sending a DELETE request to /foo?123 means you are deleting a different resource than if you were to send DELETE to /foo?456.
– Nicholas Shanks
Jan 25 '16 at 17:38
...
What requirement was the tuple designed to solve?
...e/use a tuple in a very efficient and simple way:
var person = (Id:"123", Name:"john"); //create tuble with two items
Console.WriteLine($"{person.Id} name:{person.Name}") //access its fields
Returning more than one value from a method:
public (double sum, double average) ComputeSu...
Check synchronously if file/directory exists in Node.js
...
123
Looking at the source, there's a synchronous version of path.exists - path.existsSync. Looks ...
How to pull request a wiki page on GitHub?
...
123
GitHub doesn't support pull requests for the wiki repository, only the main repository (this i...
What's the best way to get the last element of an array without deleting it?
... = $array[count($array)-1]; || 123 | 300 | 137 | 139 | 143 | 140 | 144 || 312 | 218 | 48 | 53 | 45 | 47 | 51 || ...