大约有 40,000 项符合查询结果（耗时：0.1130秒） [XML]
Extract a substring according to a pattern
...)
strapplyc(string, ":(.*)", simplify = TRUE)
## [1] "E001" "E002" "E003"
6) read.dcf
This one only works if the substrings prior to the colon are unique (which they are in the example in the question). Also it requires that the separator be colon (which it is in the question). If a different sep...
Why {} + {} is NaN only on the client side? Why not in Node.js?
...
answered Jun 24 '13 at 6:39
Benjamin GruenbaumBenjamin Gruenbaum
235k7777 gold badges459459 silver badges466466 bronze badges
...
How to set Python's default version to 3.x on OS X?
...
John R Perry
2,96011 gold badge2626 silver badges4444 bronze badges
answered Aug 25 '13 at 4:06
Santosh KumarSantosh ...
How to upload, display and save images using node.js and express [closed]
...
236
First of all, you should make an HTML form containing a file input element. You also need to set...
How to autosize a textarea using Prototype?
...t;script language="javascript">
google.load('prototype', '1.6.0.2');
</script>
</head>
<body>
<textarea id="text-area" rows="1" cols="50"></textarea>
<script type="text/javascript" language="javascript">
...
Memoization in Haskell?
... mf. This means that results like:
*Main Data.List> faster_f 123801
248604
are tolerable, but the result doesn't scale much better than that. We can do better!
First, let's define an infinite tree:
data Tree a = Tree (Tree a) a (Tree a)
instance Functor Tree where
fmap f (Tree l m r) = T...
What is the (function() { } )() construct in JavaScript?
...
876
It’s an Immediately-Invoked Function Expression, or IIFE for short. It executes immediately af...
Dealing with commas in a CSV file
....Read ) )
{
}
public CsvReader( Stream stream )
{
__reader = new StreamReader( stream );
}
public System.Collections.IEnumerable RowEnumerator
{
get {
if ( null == __reader )
throw new System.ApplicationException( "I can't sta...
Is there an easy way to request a URL in python and NOT follow redirects?
...st way to do it would be to subclass HTTPRedirectHandler and then use build_opener to override the default HTTPRedirectHandler, but this seems like a lot of (relatively complicated) work to do what seems like it should be pretty simple.
...
Can I use Objective-C blocks as properties?
... I didn't know that, thanks! ... Although I often do @synthesize myProp = _myProp
– Robert
Nov 8 '12 at 8:04
...