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How to check whether a pandas DataFrame is empty?
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This seems like a shame, since you need to know that df is a pd.DataFrame. I'd like to know the motivation for not implementing bool() on pd.DataFrame.
– Quant
Feb 14 '14 at 16:55
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How to handle multiple cookies with the same name?
...: this information from 2010 appears to be outdated, it seems browsers can now send multiple cookies in return, see answer by @Nate below for details
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Why are preprocessor macros evil and what are the alternatives?
...gers, you can't "see" what the macro translates to. So you don't actually know what is going on.
Replacement: Use enum or const T
For "function-like" macros, because the debugger works on a "per source line where you are" level, your macro will act like a single statement, no matter if it's one ...
jQuery: Get selected element tag name
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As of jQuery 1.6 you should now call prop:
$target.prop("tagName")
See http://api.jquery.com/prop/
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Expand/collapse section in UITableView in iOS
... headers that are already there will be a pain. Based on the way they work now, I am not sure you can easily get actions out of them. You could set up a cell to LOOK like a header, and setup the tableView:didSelectRowAtIndexPath to manually expand or collapse the section it is in.
I'd store an arra...
Sending an HTTP POST request on iOS
...t setURL:[NSURL URLWithString:@"http://www.abcde.com/xyz/login.aspx"]];
Now, set HTTP method (POST or GET). Write this lines as it is in your code.
[request setHTTPMethod:@"POST"];
Set HTTP header field with length of the post data.
[request setValue:postLength forHTTPHeaderField:@"Content-...
How to get random value out of an array?
...ased to mt_rand() and srand() aliased to mt_srand(). In practice it should now be good enough.
– Gras Double
Jun 29 '17 at 11:17
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How to use '-prune' option of 'find' in sh?
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+1 finally found out why I need -print at end, I can now stop adding \! -path <pattern> in addition to -prune
– Miserable Variable
May 14 '13 at 20:39
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Why is nginx responding to any domain name?
...nginx up and running with a Ruby/Sinatra app and all is well. However, I'm now trying to have a second application running from the same server and I noticed something weird. First, here's my nginx.conf:
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Retrieving the last record in each group - MySQL
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MySQL 8.0 now supports windowing functions, like almost all popular SQL implementations. With this standard syntax, we can write greatest-n-per-group queries:
WITH ranked_messages AS (
SELECT m.*, ROW_NUMBER() OVER (PARTITION BY nam...