大约有 40,000 项符合查询结果（耗时：0.0527秒） [XML]
Linux: copy and create destination dir if it does not exist
...
oops, right. But then, test may be a bash builtin (especially if written as [[ -d "$d" ]]) and mkdir can not ;-)
– Michael Krelin - hacker
Oct 7 '09 at 17:00
1
...
Convert a row of a data frame to vector
...
Might have been changed in the meantime, but today unlist allows dropping names: identical(unlist(df[1,], use.names = FALSE), as.numeric(df[1,])) (and btw df still is not a sensible name for a data.frame... ;-))
– Andri Signorell
Sep 25 '1...
Inserting string at position x of another string
...er https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/substr)
share
|
improve this answer
|
follow
|
...
How does StartCoroutine / yield return pattern really work in Unity?
...rocesses, like gameplay triggers, that do nothing most frames, but occasionally are called upon to do critical work. And you’ve got assorted processes between the two.
Whenever you’re creating a process that will take place over multiple frames – without multithreading – you need to fin...
How to validate IP address in Python? [duplicate]
...ings like "4" and "192.168" and silently pads the rest with zeros. Technically valid, I'm sure, but not quite what I expected.
– krupan
Nov 25 '08 at 23:58
6
...
What is the difference between attribute and property? [closed]
...roperties.
To further confuse things, changes to the properties will typically update the attributes.
For example, changing the element.href property will update the href attribute on the element, and that'll be reflected in a call to element.getAttribute('href').
However if you subsequently read...
Memoization in Haskell?
...tion (fix)
Let's define f, but make it use 'open recursion' rather than call itself directly.
f :: (Int -> Int) -> Int -> Int
f mf 0 = 0
f mf n = max n $ mf (n `div` 2) +
mf (n `div` 3) +
mf (n `div` 4)
You can get an unmemoized f by using fix f
This...
Using HTML in Express instead of Jade
...y use response.sendFile
app.get('/', function (req, res) {
res.sendfile(__dirname + '/index.html');
});)
From the official express api reference:
res.sendfile(path, [options], [fn]])
Transfer the file at the given path.
Automatically defaults the Content-Type response header field...
Get the index of the object inside an array, matching a condition
...lorer, there's a polyfill on the linked page.
Performance note
Function calls are expensive, therefore with really big arrays a simple loop will perform much better than findIndex:
let test = [];
for (let i = 0; i < 1e6; i++)
test.push({prop: i});
let search = test.length - 1;...
Django's SuspiciousOperation Invalid HTTP_HOST header
...
If your ALLOWED_HOSTS is set correctly, then it is possible someone is probing your site for the vulnerability by spoofing the header.
There is discussion right now by the Django developers to change this from a 500 internal server...