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How can I reverse a list in Python?
...cing, such as range(1,4)[::-1], reversed() is easier to read, runs faster, and uses substantially less memory. "
– Jim Oldfield
Aug 20 '16 at 15:55
5
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How to style the parent element when hovering a child element?
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Well, this question is asked many times before, and the short typical answer is: It cannot be done by pure CSS. It's in the name: Cascading Style Sheets only supports styling in cascading direction, not up.
But in most circumstances where this effect is wished, like in th...
Can dplyr package be used for conditional mutating?
... TRUE ~ NA_real_))
Added - arithmetic/na_if If the values are numeric and the conditions (except for the default value of NA at the end) are mutually exclusive, as is the case in the question, then we can use an arithmetic expression such that each term is multiplied by the desired result using...
django - why is the request.POST object immutable?
...nts a full set of mutation methods including __setitem__, __delitem__, pop and clear. It implements immutability by checking a flag when you call one of the mutation methods. And when you call the copy method you get another QueryDict instance with the mutable flag turned on.
For performance improve...
Using the scrollwheel in GNU screen
...tach from your screen, then screen -d -r to reattach, then ls a few times, and try to scroll back. It works for me.
What is this magic? Well, let's consult the manual pages.
screen(1) says:
termcapinfo term terminal-tweaks [window-tweaks]
[..]
The first argument specifies which terminal(s)...
Python str vs unicode types
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unicode is meant to handle text. Text is a sequence of code points which may be bigger than a single byte. Text can be encoded in a specific encoding to represent the text as raw bytes(e.g. utf-8, latin-1...).
Note that unicode is not encoded! T...
Can I add jars to maven 2 build classpath without installing them?
Maven2 is driving me crazy during the experimentation / quick and dirty mock-up phase of development.
24 Answers
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How to access cookies in AngularJS?
...e AngularJS way to access cookies? I've seen references to both a service and a module for cookies, but no examples.
9 A...
【BLE技术内幕】BLE技术揭秘 - 创客硬件开发 - 清泛IT论坛，有思想、有深度
文章源自：http://doc.iotxx.com/index.php?title=BLE技术揭秘
BLE技术揭秘
BLE是低功耗蓝牙的英文缩写（Bluetooth Low Energy），是蓝牙4.0版本起开始支持的新的、低功耗版本的蓝牙技术规范。蓝牙技术联盟（Bluetooth SIG）在2010年发布了跨...
Iterate a list as pair (current, next) in Python
...ometimes need to iterate a list in Python looking at the "current" element and the "next" element. I have, till now, done so with code like:
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