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Opposite of %in%: exclude rows with values specified in a vector
A categorical variable V1 in a data frame D1 can have values represented by the letters from A to Z. I want to create a subset D2, which excludes some values, say, B, N and T. Basically, I want a command which is the opposite of %in%
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What does ||= (or-equals) mean in Ruby?
...gnment operator. It means if a is undefined or falsey, then evaluate b and set a to the result. Equivalently, if a is defined and evaluates to truthy, then b is not evaluated, and no assignment takes place. For example:
a ||= nil # => nil
a ||= 0 # => 0
a ||= 2 # => 0
foo = false # => ...
How do I make a redirect in PHP?
... click $link here if redirect dont happen" Some broser, and some browser's settings, may fail that redirect.
– Strae
Apr 20 '09 at 15:49
3
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Linux环境离线安装docker&docker-compose - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...服务的服务器上，解压下载的docker安装包；
sudo tar -xvf docker-26.1.4-x86_64.tgz
# 给docker执行文件赋予可执行权限
sudo chmod 755 -R docker
# 复制docker到/usr/bin/目录下，使docker命令可以执行
sudo cp docker/* /usr/bin/
# 清理...
What does 'wb' mean in this code, using Python?
... editor after snippets, if snippets enabled
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How to write LaTeX in IPython Notebook?
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This came up in a search I was just doing, found a better solution with some more searching, IPython notebooks now have a %%latex magic that makes the whole cell Latex without the $$ wrapper for each line.
Refer notebook tour for Rich Display System
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Javascript How to define multiple variables on a single line?
...o lines?
var a, b, c, d; // All in the same scope
a = b = c = d = 1; // Set value to all.
The reason why, is to preserve the local scope on variable declarations, as this:
var a = b = c = d = 1;
will lead to the implicit declarations of b, c and d on the window scope.
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String replacement in Objective-C
...multiple string replacement:
NSString *s = @"foo/bar:baz.foo";
NSCharacterSet *doNotWant = [NSCharacterSet characterSetWithCharactersInString:@"/:."];
s = [[s componentsSeparatedByCharactersInSet: doNotWant] componentsJoinedByString: @""];
NSLog(@"%@", s); // => foobarbazfoo
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Turning off auto indent when pasting text into vim
...f autoindent when you paste code, there's a special "paste" mode.
Type
:set paste
Then paste your code. Note that the text in the tooltip now says -- INSERT (paste) --.
After you pasted your code, turn off the paste-mode, so that auto-indenting when you type works correctly again.
:set nopas...
How to sort my paws?
...this answer, but I need to elaborate a bit on some things... (Though I may set a record for the longest non-spam stackoverflow answer ever!)
As a side note, I'm using the full dataset that Ivo provided a link to in his original question. It's a series of rar files (one-per-dog) each containing sev...