大约有 46,000 项符合查询结果（耗时：0.0528秒） [XML]
Counting the number of elements with the values of x in a vector
... 2 2 1 1 2 1 2 1 3 1 1 1 1
Then you can subset it:
> a[names(a)==435]
435
3
Or convert it into a data.frame if you're more comfortable working with that:
> as.data.frame(table(numbers))
numbers Freq
1 4 2
2 5 1
3 23 2
4 3...
How to re-open an issue in github?
I have reported an issue to a project. Now owner changed it state to closed, but how can I change it to open again ?
I read somewhere that I need rights for push and pull operation. Is that true ?
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How does a public key verify a signature?
...e on how public/private keys work. I understand that a sender may add a digital signature to a document using his/her private key to essentially obtain a hash of the document, but what I do not understand is how the public key can be used to verify that signature.
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How to download a file with Node.js (without using third-party libraries)?
How do I download a file with Node.js without using third-party libraries ?
27 Answers
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What is the need of JSF, when UI can be achieved with JavaScript libraries such as jQuery and Angula
I was reading about JSF that its a UI framework and provides some UI components. But how is it better or different from number of components that are available from jQueryUI, AngularJS, ExtJS, or even plain HTML, CSS and JavaScript.
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iPhone Keyboard Covers UITextField
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The usual solution is to slide the field (and everything above it) up with an animation, and then back down when you are done. You may need to put the text field and some of the other items into another view and slide the view as a unit. (I call these things "plates" as in "tectonic pl...
JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
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You can use an utility function like this:
get = function(obj, key) {
return key.split(".").reduce(function(o, x) {
return (typeof o == "undefined" || o === null) ? o : o[x];
}, obj);
}
Usage:
get(user, 'loc.lat') // 50...
Python syntax for “if a or b or c but not all of them”
I have a python script that can receive either zero or three command line arguments. (Either it runs on default behavior or needs all three values specified.)
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OSGi, Java Modularity and Jigsaw
...p over and over again, and so I finally set aside some time to brush up on it.
3 Answers
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What is the easiest way to remove all packages installed by pip?
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I've found this snippet as an alternative solution. It's a more graceful removal of libraries than remaking the virtualenv:
pip freeze | xargs pip uninstall -y
In case you have packages installed via VCS, you need to exclude those lines and remove the packages manually (e...