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Split a vector into chunks in R
...e here. Although the OP's question was to split into chunks of equal size, if the vector happens not to be a multiple of the divisor, the last chink will have a different size than chunk. To split into n-chunks I used max <- length(d)%/%n. I used this with a vector of 31 strings and obtained a li...
Can I force pip to reinstall the current version?
...ce-reinstall <package>
When upgrading, reinstall all packages even if they are already up-to-date.
pip install -I <package>
pip install --ignore-installed <package>
Ignore the installed packages (reinstalling instead).
...
How do you properly determine the current script directory in Python?
...e; normally you should be using the module infrastructure to load scripts. If you must use these methods, I suggest setting __file__ in the globals you pass to the script so it can read that filename.
There's no other way to get the filename in execed code: as you note, the CWD may be in a complete...
How to get visitor's location (i.e. country) using geolocation? [duplicate]
...
You don't need to locate the user if you only need their country. You can look their IP address up in any IP-to-location service (like maxmind, ipregistry or ip2location). This will be accurate most of the time.
If you really need to get their location, you ...
ruby on rails f.select options with custom attributes
...=>c.currency_code}] },
selected_key = f.object.country_id) %>
If you need grouped options, you can use the grouped_options_for_select helper, like this (if @continents is an array of continent objects, each having a countries method):
<%= f.select :country_id, grouped_options_for_se...
Can I control the location of .NET user settings to avoid losing settings on application upgrade?
...As for the second question, it depends on how you deploy the application. If you deploy via a .msi, then there are two hashes in the properties of the setup project (that the msi is built from), the 'upgrade code' and the 'product code'. These determine how the msi can be installed, and if it upgr...
Alter MySQL table to add comments on columns
...tation for ALTER TABLE and it does not seem to include a way to add or modify a comment to a column. How can I do this?
5 ...
What is process.env.PORT in Node.js?
....PORT || 3000 means: whatever is in the environment variable PORT, or 3000 if there's nothing there.
So you pass that app.listen, or to app.set('port', ...), and that makes your server be able to accept a parameter from the environment what port to listen on.
If you pass 3000 hard-coded to app.lis...
How to git clone a specific tag
...th 1 --branch <tag_name> <repo_url>
--depth 1 is optional but if you only need the state at that one revision, you probably want to skip downloading all the history up to that revision.
share
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...
Yes/No message box using QMessageBox
...it?",
QMessageBox::Yes|QMessageBox::No);
if (reply == QMessageBox::Yes) {
qDebug() << "Yes was clicked";
QApplication::quit();
} else {
qDebug() << "Yes was *not* clicked";
}
}
Should work on Qt 4 and 5, requires QT += widgets on Qt 5, ...