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Extracting numbers from vectors of strings
...ion is an indirect way of getting to the solution. If you want to retrieve all the numbers, I recommend gregexpr:
matches <- regmatches(years, gregexpr("[[:digit:]]+", years))
as.numeric(unlist(matches))
If you have multiple matches in a string, this will get all of them. If you're only intere...
Align image in center and middle within div
...00%; height:100%">
<img src="http://www.garcard.com/images/garcard_symbol.png">
</div>
JSFiddle
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How to loop over files in directory and change path and add suffix to filename
...le of notes first: when you use Data/data1.txt as an argument, should it really be /Data/data1.txt (with a leading slash)? Also, should the outer loop scan only for .txt files, or all files in /Data? Here's an answer, assuming /Data/data1.txt and .txt files only:
#!/bin/bash
for filename in /Data/*...
Can I list-initialize a vector of move-only type?
...nitializer list elements in the current revision of the language.
Specifically, we have:
typedef const E& reference;
typedef const E& const_reference;
typedef const E* iterator;
typedef const E* const_iterator;
const E* begin() const noexcept; // first element
const E* end() const noexce...
Changes in import statement python3
...a single function. In Python 2 you were permitted to be semi-lazy:
def sin_degrees(x):
from math import *
return sin(degrees(x))
Note that it already triggers a warning in Python 2:
a.py:1: SyntaxWarning: import * only allowed at module level
def sin_degrees(x):
In modern Python 2 co...
How do I shuffle an array in Swift?
...Distance` in < Swift 4.1
let d: Int = numericCast(arc4random_uniform(numericCast(unshuffledCount)))
let i = index(firstUnshuffled, offsetBy: d)
swapAt(firstUnshuffled, i)
}
}
}
extension Sequence {
/// Returns an array with the contents of this...
OceanBase使用libeasy原理源码分析：客户端 - 数据库(内核) - 清泛网 - 专...
...端》，作为客户端使用时，会涉及到一些数据结构，easy_session_t, easy_client_t, easy_hash_t, easy_hash_list_t等。
easy_session_t用来封装一个要发出去的请求，easy_client_t用来封装一个TCP连接的发起端，easy_hash_t是一个哈希表，easy_hash_list_t是...
How to read environment variables in Scala
...
I would also prefer Properties. It allows to retrieve Optionals, and has names for commonly used properties.
– ppopoff
Dec 17 '15 at 14:46
...
How to draw a line in android
...rself just simple and clean add the line in xml.
<View
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="@android:color/black" />
The example code I provided will generate a line that fills the screen in width and has a height of one dp.
If you have ...
What are all the escape characters?
I know some of the escape characters in Java, e.g.
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