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What does the JSLint error 'body of a for in should be wrapped in an if statement' mean?
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First of all, never use a for in loop to enumerate over an array. Never. Use good old for(var i = 0; i<arr.length; i++).
The reason behind this is the following: each object in JavaScript has a special field called prototype. Everything you add to...
Python argparse: default value or specified value
...efault if the user specifies a value. Is there already an action available for this?
3 Answers
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adito-gateway -华为云免费SSL VPN解决方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...tar.gz
解压出来后，移动到usr目录
[root@adito mnt]# mv jdk1.7.0_17 /usr
配置java 参数
alternatives --install /usr/bin/java java /usr/jdk1.7.0_17/jre/bin/java 20000
alternatives --install /usr/bin/javaws javaws /usr/jdk1.7.0_17/jre/bin/javaws 20000
alternatives --install /usr/...
How does the main() method work in C?
...age started out as hacks which just happened to work.
Multiple signatures for main, as well as variable-length argument lists, is one of those features.
Programmers noticed that they can pass extra arguments to a function, and nothing bad happens with their given compiler.
This is the case if the...
Temporarily disable auto_now / auto_now_add
...e recently faced this situation while testing my application. I needed to "force" an expired timestamp. In my case I did the trick by using a queryset update. Like this:
# my model
class FooBar(models.Model):
title = models.CharField(max_length=255)
updated_at = models.DateTimeField(auto_no...
Why is it impossible to override a getter-only property and add a setter? [closed]
...ly declared that Bar has to be a read-only property. It doesn't make sense for derivations to break this contract and make it read-write.
I'm with Microsoft on this one.
Let's say I'm a new programmer who has been told to code against the Baseclass derivation. i write something that assumes that Ba...
JavaScript open in a new window, not tab
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Give the window a 'specs' parameter with width/height. See here for all the possible options.
window.open(url, windowName, "height=200,width=200");
When you specify a width/height, it will open it in a new window instead of a tab.
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JavaScript and Threads
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See http://caniuse.com/#search=worker for the most up-to-date support info.
The following was the state of support circa 2009.
The words you want to google for are JavaScript Worker Threads
Apart from from Gears there's nothing available right now, but there...
Removing duplicates from a list of lists
...]]
>>> import itertools
>>> k.sort()
>>> list(k for k,_ in itertools.groupby(k))
[[1, 2], [3], [4], [5, 6, 2]]
itertools often offers the fastest and most powerful solutions to this kind of problems, and is well worth getting intimately familiar with!-)
Edit: as I menti...
Converting strings to floats in a DataFrame
...d.to_numeric as described in other
answers.
This is available in 0.11. Forces conversion (or set's to nan)
This will work even when astype will fail; its also series by series
so it won't convert say a complete string column
In [10]: df = DataFrame(dict(A = Series(['1.0','1']), B = Series(['1.0...