大约有 45,000 项符合查询结果（耗时：0.0860秒） [XML]
delete a.x vs a.x = undefined
...a.x = undefined
means that a.hasOwnProperty("x") will still return true, and therefore, it will still show up in a for in loop, and in Object.keys()
delete a.x
means that a.hasOwnProperty("x") will return false
The way that they are the same is that you can't tell if a property exists by testi...
How can I get the client's IP address in ASP.NET MVC?
I'm totally new to the ASP.NET MVC stack, and I was wondering what happened to the simple Page object and the Request ServerVariables object?
...
R: += (plus equals) and ++ (plus plus) equivalent from c++/c#/java, etc.?
... sure. I'm with you there. I ran into this issue working on a project once and it took me an hour to find the issue.
– knrumsey
Feb 17 '19 at 22:38
...
How do you calculate the average of a set of circular data? [closed]
...
Compute unit vectors from the angles and take the angle of their average.
share
|
improve this answer
|
follow
|
...
What's the best way to get the last element of an array without deleting it?
... many different options. To be able to choose from them I needed to understand their behavior and performance. In this answer I will share my findings with you, benchmarked against PHP versions 5.6.38, 7.2.10 and 7.3.0RC1 (expected Dec 13 2018).
The options (<<option code>>s) I will tes...
xkcd style graphs in MATLAB
...Rody Oldenhuis' solution). The second way is to create a non-jittery plot, and use imtransform to apply a random distortion to the image. This has the advantage that you can use it with any plot, but you will end up with an image, not an editable plot.
I'll show #2 first, and my attempt at #1 below...
How to create a HashMap with two keys (Key-Pair, Value)?
...= 31 * result + y;
return result;
}
}
Implementing equals() and hashCode() is crucial here. Then you simply use:
Map<Key, V> map = //...
and:
map.get(new Key(2, 5));
Table from Guava
Table<Integer, Integer, V> table = HashBasedTable.create();
//...
table.get(2, 5);...
Number.sign() in javascript
...its absolute value also gives its sign. Using the short-circuiting logical AND operator allows us to special-case 0 so we don't end up dividing by it:
var sign = number && number / Math.abs(number);
share
...
Why use apparently meaningless do-while and if-else statements in macros?
...
The do ... while and if ... else are there to make it so that a
semicolon after your macro always means the same thing. Let's say you
had something like your second macro.
#define BAR(X) f(x); g(x)
Now if you were to use BAR(X); in an if ...
What Haskell representation is recommended for 2D, unboxed pixel arrays with millions of pixels?
...ge-processing problems in Haskell. I'm working with both bitonal (bitmap) and color images with millions of pixels. I have a number of questions:
...