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Pandas every nth row
...] # Excludes every 3rd row starting from 0
df2 = df[df.index % 3 == 0] # Selects every 3rd raw starting from 0
This arithmetic based sampling has the ability to enable even more complex row-selections.
This assumes, of course, that you have an index column of ordered, consecutive, integers star...
Debugging with command-line parameters in Visual Studio
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Make sure you have the correct Configuration selected in the dropdown at the top of the Property pages, i.e. the same configuration as the one you are trying to run.
– Steve Smith
Jan 4 '18 at 14:51
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Undock Chrome Developer Tools
...er button
You can also undock/dock-to-left/dock-to-right/dock-to-bottom from the Command Menu. Press Cmd+Shift+P (Mac) or Cmd+Shift+P (Windows, Linux, Chrome OS) to open the Command Menu, then start typing bottom/left/right/undock.
DevTools documentation on docking: https://developers.google.c...
Symbolic links and synced folders in Vagrant
... went back and removed the SharedFoldersEnableSymlinksCreate configuration from the Vagrantfile, and everything was still fine.
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follow
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Store boolean value in SQLite
...TO foo VALUES("0.0");
sqlite> INSERT INTO foo VALUES("1.0");
sqlite> select mycolumn, typeof(mycolumn) from foo;
0|integer
1|integer
0|integer
1|integer
0|integer
1|integer
and some that will fail:
sqlite> INSERT INTO foo VALUES("-1");
Error: constraint failed
sqlite> INSERT INTO foo ...
GROUP_CONCAT ORDER BY
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You can use ORDER BY inside the GROUP_CONCAT function in this way:
SELECT li.client_id, group_concat(li.percentage ORDER BY li.views ASC) AS views,
group_concat(li.percentage ORDER BY li.percentage ASC)
FROM li GROUP BY client_id
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Does anyone have benchmarks (code & results) comparing performance of Android apps written in Xamari
...t know why it's so much slower. One possibility is that marshaling strings from native to Java may be faster on Android than native to C# is on Xamarin.
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How to rename items in values() in Django?
... a bit hacky, but you could use the extra method:
MyModel.objects.extra(
select={
'renamed_value': 'cryptic_value_name'
}
).values(
'renamed_value'
)
This basically does SELECT cryptic_value_name AS renamed_value in the SQL.
Another option, if you always want the renamed version but the d...
Why is conversion from string constant to 'char*' valid in C but invalid in C++
...https%3a%2f%2fstackoverflow.com%2fquestions%2f20944784%2fwhy-is-conversion-from-string-constant-to-char-valid-in-c-but-invalid-in-c%23new-answer', 'question_page');
}
);
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Select elements by attribute in CSS
Is it possible to select elements in CSS by their HTML5 data attributes (for example, data-role )?
5 Answers
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