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Why is `[` better than `subset`?
When I need to filter a data.frame, i.e., extract rows that meet certain conditions, I prefer to use the subset function:
...
Some projects cannot be imported because they already exist in the workspace error in Eclipse
I am trying to import a project that me and my co-worker have been working on.. and keep getting this error after I select-- "import" then "import existing project" then click archive file, and then I click next, and this error comes up:
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How do I create directory if none exists using File class in Ruby?
... are not already present:
require 'fileutils'
dirname = File.dirname(some_path)
unless File.directory?(dirname)
FileUtils.mkdir_p(dirname)
end
Edit: Here is a solution using the core libraries only (reimplementing the wheel, not recommended)
dirname = File.dirname(some_path)
tokens = dirname....
Asynchronously wait for Task to complete with timeout
I want to wait for a Task<T> to complete with some special rules:
If it hasn't completed after X milliseconds, I want to display a message to the user.
And if it hasn't completed after Y milliseconds, I want to automatically request cancellation .
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How to import an existing X.509 certificate and private key in Java keystore to use in SSL?
...j's 'workaround' link to this 2008 post: cunning.sharp.fm/2008/06/importing_private_keys_into_a.html
– cloudsurfin
Feb 11 '16 at 0:44
2
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Create empty file using python [duplicate]
I'd like to create a file with path x using python. I've been using os.system(y) where y = 'touch %s' % (x) . I've looked for a non-directory version of os.mkdir , but I haven't been able to find anything. Is there a tool like this to create a file without opening it, or using system or popen/...
How do I hide a menu item in the actionbar?
... calling menu.findItem()) and call setVisible() on it. The answers by suhas_sm and by P1r4nh4 present the correct approach.
– Ted Hopp
Jun 24 '14 at 17:33
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How do I get the last inserted ID of a MySQL table in PHP?
...ng PDO, use PDO::lastInsertId.
If you're using Mysqli, use mysqli::$insert_id.
If you're still using Mysql:
Please, don't use mysql_* functions in new code. They are no longer maintained and are officially deprecated. See the red box? Learn about prepared statements instead, and use PDO or MyS...
Is it OK to use == on enums in Java?
Is it OK to use == on enums in Java, or do I need to use .equals() ? In my testing, == always works, but I'm not sure if I'm guaranteed of that. In particular, there is no .clone() method on an enum, so I don't know if it is possible to get an enum for which .equals() would return a diffe...
How do I send a POST request with PHP?
...lencoded\r\n",
'method' => 'POST',
'content' => http_build_query($data)
)
);
$context = stream_context_create($options);
$result = file_get_contents($url, false, $context);
if ($result === FALSE) { /* Handle error */ }
var_dump($result);
See the PHP manual for more inf...