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How do you calculate the average of a set of circular data? [closed]
...xample, I might have several samples from the reading of a compass. The problem of course is how to deal with the wraparound. The same algorithm might be useful for a clockface.
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What's the fastest way to loop through an array in JavaScript?
I learned from books that you should write for loop like this：
22 Answers
22
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How to select an element with 2 classes [duplicate]
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You can chain class selectors without a space between them:
.a.b {
color: #666;
}
Note that, if it matters to you, IE6 treats .a.b as .b, so in that browser both div.a.b and div.b will have gray text. See this answer for a comparison between proper browsers and I...
Python if-else short-hand [duplicate]
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The most readable way is
x = 10 if a > b else 11
but you can use and and or, too:
x = a > b and 10 or 11
The "Zen of Python" says that "readability counts", though, so go for the first way.
Also, the and-or trick will fail if ...
scrapy xpath抓取节点的文本innerText、innerHTML、outerHTML - 更多技术 -...
...取节点的文本innerText、innerHTML、outerHTML假设抓取：<p> xx<b>x< b>< p> 抓取p节点本身，得到的内容：<p>xx<b>x< b>< p>response xpath(& 39; div[@class="question"] div[2] div[2] div[1] p[1]& 39;) extract() 抓 假设抓取：
<p>
xx<b>x</b>
</p>
scrapy代码：
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View list of all JavaScript variables in Google Chrome Console
In Firebug, the DOM tab shows a list of all your public variables and objects. In Chrome's console you have to type the name of the public variable or object you want to explore.
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Regular vs Context Free Grammars
...ying for my computing languages test, and there's one idea I'm having problems wrapping my head around.
8 Answers
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What are some (concrete) use-cases for metaclasses?
...e a class that handles non-interactive plotting, as a frontend to Matplotlib. However, on occasion one wants to do interactive plotting. With only a couple functions I found that I was able to increment the figure count, call draw manually, etc, but I needed to do these before and after every plot...
How to effectively work with multiple files in Vim
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Why not use tabs (introduced in Vim 7)?
You can switch between tabs with :tabn and :tabp,
With :tabe <filepath> you can add a new tab; and with a regular :q or :wq you close a tab.
If you map :tabn and :tabp to your F7/F8 keys you ca...
SQL Inner-join with 3 tables?
I'm trying to join 3 tables in a view; here is the situation:
12 Answers
12
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