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Does the ternary operator exist in R?
... 2*3 : 4
[1] 6
> y
[1] 1
> y <- (1 ? 2*3 : 4)
> y
[1] 6
Finally, you can do very similar way with c:
`?` <- function(x, y) {
xs <- as.list(substitute(x))
if (xs[[1]] == as.name("<-")) x <- eval(xs[[3]])
r <- eval(sapply(strsplit(deparse(substitute(y)), ":"), fun...
Changing the image source using jQuery
...
Yes. This finally did the trick. .destroy() doesn't go nearly far enough. Nuking all the html and than init again actually works when swapping out images of various sizes and such.
– Matt J.
Apr 11 '...
Find out how much memory is being used by an object in Python [duplicate]
...and internal structures related to object types and garbage collection. Finally, some python objects have non-obvious behaviors. For instance, lists reserve space for more objects than they have, most of the time; dicts are even more complicated since they can operate in different ways (they have a ...
Chrome Dev Tools: How to trace network for a link that opens a new tab?
...e://net-export in the latest version of Chrome) for a detailed overview of all network events happening in your browser.
Other possible solution, depending on your specific problem, may be to enable 'Preserve log' on the 'Network' tab:
and force all links to open in the same tab by executing ...
How to show all parents and subclasses of a class in IntelliJ IDEA?
...r is over a class variable, I can do Ctrl + T to have a popup that shows all its parents and subclasses. What is the equivalent in IntelliJ?
...
Where are $_SESSION variables stored?
...ariable storage is determined by PHP's session.save_path configuration. Usually this is /tmp on a Linux/Unix system. Use the phpinfo() function to view your particular settings if not 100% sure by creating a file with this content in the DocumentRoot of your domain:
<?php
phpinfo();
?>
...
Extension · App Inventor 2 中文网
...误码, errorMessage: 错误信息
Methods
CallFunction(函数名称,params)
调用云函数。functionName: 函数名, params: JSON参数(可为空)
CloudBaseMySQL
查询、插入、更新和删除均通过对应的成功事件返回结果...
How to clone all remote branches in Git?
..., StackOverflow has grown quite a bit in terms of quality.
This "answer" really does not address the question at all. In fact, few of the top-voted answers do.
Here are two answers that will work as of git v2.28.0:
https://stackoverflow.com/a/4754797/430062
https://stackoverflow.com/a/7216269/43006...
How to add hyperlink in JLabel?
...the link color to purple after being clicked, if that seemed useful. It's all self contained, you simply call:
SwingLink link = new SwingLink("Java", "http://java.sun.com");
mainPanel.add(link);
share
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Coalesce function for PHP?
...HP 7 introduced a real coalesce operator:
echo $_GET['doesNotExist'] ?? 'fallback'; // prints 'fallback'
If the value before the ?? does not exists or is null the value after the ?? is taken.
The improvement over the mentioned ?: operator is, that the ?? also handles undefined variables without...