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How do I measure time elapsed in Java? [duplicate]
...digits of a decimal fraction of a second. For example, 2016-03-12T04:29:39.123456789Z.
Both the old java.util.Date/.Calendar classes and the Joda-Time classes have millisecond resolution (3 digits of fraction). For example, 2016-03-12T04:29:39.123Z.
In Java 8, the current moment is fetched with up...
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 the difference between Ruby 1.8 and Ruby 1.9
..._s
=> "[1, 2, 3]"
Ruby 1.8.6
irb(main):001:0> [1,2,3].to_s
=> "123"
Action: Use .join instead
Colon No Longer Valid In When Statements
Ruby 1.9
irb(main):001:0> case 'a'; when /\w/: puts 'word'; end
SyntaxError: (irb):1: syntax error, unexpected ':',
expecting keyword_then or '...
Accessing an SQLite Database in Swift
... Id = ?") != .Ok )
{
/* handle error */
}
statement.bindInt(1, value: 123);
if ( statement.step() == .Row )
{
/* do something with statement */
var id:Int = statement.getIntAt(0)
var stringValue:String? = statement.getStringAt(1)
var boolValue:Bool = statement.getBoolAt(2)
...
Throwing the fattest people off of an overloaded airplane.
...0.3, 157.4, 138.9, 143.0, 145.1, 125.1, 138.5, 143.8, 146.8, 140.1, 136.9, 123.1, 140.2, 153.6, 138.6, 146.5, 143.6, 130.8, 155.7, 128.9, 143.8, 124.0, 134.0, 145.0, 136.0, 121.2, 133.4, 144.0, 126.3, 127.0, 148.3, 144.9, 128.1]
...
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
...
How do I profile memory usage in Python?
...
123
This one has been answered already here: Python memory profiler
Basically you do something li...
What is the best collation to use for MySQL with PHP? [closed]
..., `notes`) VALUES
(1, NULL, '0000-00-00 00:00:00', '2014-08-25 03:00:36', '1234567890', '12345678901234567890', '1234567890123456789012345678901234567890', '1234567890123456789012345678901234567890', '123456789012345678901234567890123456789012345678901234567890123456789012345678901234567890123456789...
Choosing Java vs Python on Google App Engine
...
123
I'm biased (being a Python expert but pretty rusty in Java) but I think the Python runtime of ...
App Inventor 2 CustomWebView 拓展：高级版Web浏览器，完美浏览现代Web前...
...rl的页面，这款拓展统统解决。
.aix 拓展下载：
cn.fun123.CustomWebView.aix
基础使用方法：
例如，使用此拓展访问 react 写的网页，效果如下：
而使用原生的Web浏览器则无法访问：
属性
AdHosts
Sets the a...