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Change R default library path using .libPaths in Rprofile.site fails to work
...dows, not as an administrator. When I install a package, the following command doesn't work:
15 Answers
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What's the difference between isset() and array_key_exists()? [duplicate]
...n an array, whereas isset will only return true if the key/variable exists and is not null.
$a = array('key1' => 'フーバー', 'key2' => null);
isset($a['key1']); // true
array_key_exists('key1', $a); // true
isset($a['key2']); // false
array_key_exists('key2', $a...
MySQL case insensitive select
...f a MySQL SELECT query is case sensitive or case insensitive by default? And if not, what query would I have to send so that I can do something like:
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Python: How to ignore an exception and proceed? [duplicate]
I have a try...except block in my code and When an exception is throw. I really just want to continue with the code because in that case, everything is still able to run just fine. The problem is if you leave the except: block empty or with a #do nothing, it gives you a syntax error. I can't use con...
What is the fastest method for selecting descendant elements in jQuery?
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Method 1 and method 2 are identical with the only difference is that method 1 needs to parse the scope passed and translate it to a call to $parent.find(".child").show();.
Method 4 and Method 5 both need to parse the selector and th...
How to avoid explicit 'self' in Python?
...ying self. The result is there's never any confusion over what's a member and what's not, even without the full class definition visible. This leads to useful properties, such as: you can't add members which accidentally shadow non-members and thereby break code.
One extreme example: you can writ...
What exactly is a Maven Snapshot and why do we need it?
I am a bit confused about the meaning of a Maven Snapshot and why we build one?
13 Answers
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Can I change multiplier property for NSLayoutConstraint?
I created two views in one superview, and then added constraints between views:
13 Answers
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创建自定义 TinyWebDB 服务 · App Inventor 2 中文网
...ar phone, TinyWebDB can be used to facilitate communication between phones and apps (e.g., multi-player games).
By default, the TinyWebDB component stores data on a test service provided by App Inventor, http://tinywebdb.appinventor.mit.edu/ . This service is helpful for testing, but it is shared b...
GitHub clone from pull request?
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You can clone the branch you want by using the -b option and for pull request:
git clone https://github.com/user_name/repo_name.git -b feature/pull_request_name dir_name
In your case, the branch you want to clone is the source branch of the pull request (feature/mongoose-support...