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Why prefer two's complement over sign-and-magnitude for signed numbers?
...o add them.
Two's complement addition is very simple. You add numbers normally and any carry bit at the end is discarded. So they're added as follows:
0010
+ 1111
=10001
= 0001 (discard the carry)
0001 is 1, which is the expected result of "2+(-1)".
But in your "intuitive" method, adding is m...
Make $JAVA_HOME easily changable in Ubuntu [closed]
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Put the environment variables into the global /etc/environment file:
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export JAVA_HOME=/usr/lib/jvm/java-1.5.0-sun
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Execute "source /etc/environment" in every shell where you want the variables to be updated:
$ source /etc/environment
Check that it works:
$ e...
What is the most efficient way to deep clone an object in JavaScript?
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Native deep cloning
It's called "structured cloning", works experimentally in Node 11 and later, and hopefully will land in browsers. See this answer for more details.
Fast cloning with data loss - JSON.parse/stringify
If you do not use Dates, funct...
Query EC2 tags from within instance
...the ec2-api-tools package, but I got nothing but 404's when I tried to install it.
– Edward Falk
Apr 8 '12 at 19:39
2
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__getattr__ on a module
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A while ago, Guido declared that all special method lookups on
new-style classes bypass __getattr__ and __getattribute__. Dunder methods had previously worked on modules - you could, for example, use a module as a context manager simply by defining __enter__...
What's the simplest way to subtract a month from a date in Python?
...at what they want can be done just by dt - timedelta(days=dt.day) As originally phrased though it sounded like they wanted to be able to subtract an arbitrary number of months and that is a bit harder.
– Duncan
Sep 19 '19 at 14:27
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Objective-C : BOOL vs bool
..., you can assume that BOOL is a char. You can use the (C99) bool type, but all of Apple's Objective-C frameworks and most Objective-C/Cocoa code uses BOOL, so you'll save yourself headache if the typedef ever changes by just using BOOL.
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Named routes _path vs _url
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As the other answers explain, you should use _url in email links, etc.
But I would like to add that you should also use _url in redirects, as explained here:
https://www.ruby-forum.com/topic/101346#221052
and, here:
http://viget.com/extend/rails-named-routes-path-vs-url
You can also t...
Remove ALL styling/formatting from hyperlinks
...ting it, you COULD use !important, but you shouldn't. It's a bad habit to fall into.
.nav a { color:green !important; } /*I'm a bad person and shouldn't use !important */
Then it'll always be green, irrelevant of any other rule.
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How do I clear only a few specific objects from the workspace?
I would like to remove some data from the workspace. I know the "Clear All" button will remove all data. However, I would like to remove just certain data.
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