大约有 10,000 项符合查询结果（耗时：0.0187秒） [XML]
Count number of occurences for each unique value
...1,2, 2, 2), 25))
library("plyr")
data_frame <- ddply(data_frame, .(v), transform, n = length(v))
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String.IsNullOrWhiteSpace in LINQ Expression
...is processed by a LINQ provider to deliver an optimized query. During this transformation not all C# statements are supported, as it either is not possible to translate them to a back-end specific query (e.g. SQL) or because the implementer did not foresee the need for the statement.
In contrast I...
在线云编程:WebIDE - IT产品资讯 - 清泛网 - 专注IT技能提升
在线云编程:WebIDE云编程 WebIDE只需一个浏览器，你就可以写代码啦，并且可以进行云端编译、运行结果。没错，编码已经进入云时代，由初创公司扣钉网络推出WebIDE，可以实现云端编程。暂略。
In which situations do we need to write the __autoreleasing ownership qualifier under ARC?
... the declaration means __strong, implicitly:
NSError * e = nil;
Will be transformed to:
NSError * __strong error = nil;
When you call your save method:
- ( BOOL )save: ( NSError * __autoreleasing * );
The compiler will then have to create a temporary variable, set at __autoreleasing. So:
N...
Get item in the list in Scala?
...apply parentheses surrounding one or more values to a variable, Scala will transform the code into an invocation of a method named apply on that variable. So greetStrings(i) gets transformed into greetStrings.apply(i). Thus accessing an element of an array in Scala is simply a method call like any o...
How can you find the height of text on an HTML canvas?
...
EDIT: Are you using canvas transforms? If so, you'll have to track the transformation matrix. The following method should measure the height of text with the initial transform.
EDIT #2: Oddly the code below does not produce correct answers when I ru...
CSS center display inline block?
...relative;
}
.childDiv {
position: absolute;
left: 50%;
transform: translateX(-50%);
}
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How can I save an image with PIL?
...Python image library (PIL) using a post I found earlier to perform fourier transforms of images and I can't get the save function to work. The whole code works fine but it just wont save the resulting image:
...
How do you represent a graph in Haskell?
...Huet's Zipper
Hoopl: A Modular, Reusable Library for Dataflow Analysis and Transformation
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Which is the correct C# infinite loop, for (;;) or while (true)? [closed]
...
The C# compiler will transform both
for(;;)
{
// ...
}
and
while (true)
{
// ...
}
into
{
:label
// ...
goto label;
}
The CIL for both is the same. Most people find while(true) to be easier to read and understand. for(;;) i...