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How to check if a column exists in Pandas
...urly-braces syntax.
Or, you can use a list comprehension, as in:
if all([item in df.columns for item in ['A','C']]):
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How do I access the $scope variable in browser's console using AngularJS?
...).scope().myVar = 5;
angular.element(myDomElement).scope().myArray.push(newItem);
// Update page to reflect changed variables
angular.element(myDomElement).scope().$apply();
Or if you're using jQuery, this does the same thing...
$('#elementId').scope();
$('#elementId').scope().$apply();
Anothe...
What's the difference between RANK() and DENSE_RANK() functions in oracle?
...ssigned the same rank, with the next ranking(s) skipped. So, if you have 3 items at rank 2, the next rank listed would be ranked 5.
DENSE_RANK again gives you the ranking within your ordered partition, but the ranks are consecutive. No ranks are skipped if there are ranks with multiple items.
As f...
Search and replace in bash using regular expressions
...ing bash substitutions to be more than 3x faster than calling sed for each item in my loop.
– rr-
Oct 11 '14 at 13:36
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Bash array with spaces in elements
...
There must be something wrong with the way you access the array's items. Here's how it's done:
for elem in "${files[@]}"
...
From the bash manpage:
Any element of an array may be referenced using ${name[subscript]}. ... If subscript is @ or *, the word expands to all members of name....
Is it better to use C void arguments “void foo(void)” or not “void foo()”? [duplicate]
.... Far from suggesting that () is the way to do varargs, I'm saying that it best to avoid varargs altogether.
– Daniel Earwicker
Jul 22 '09 at 11:52
2
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How to Decrease Image Brightness in CSS
...mething brighter or darker will depend on the background colour behind the item you're changing the opacity of. Contrary to what you say, you can make something darker by increasing the opacity if you put it on a black background. A 99% transparent image on a black background will appear almost blac...
Search stops working for “Entire Solution”
... Studio a long time and it never seems to get fixed.
See this MS Connect item from 2004: http://connect.microsoft.com/VisualStudio/feedback/details/105511/find-in-files-says-no-files-were-found-to-look-in-find-was-stopped
I couldn't believe they still hadn't fixed it in VS2010 - but it's still th...
Fastest way to determine if an integer's square root is an integer
...
You'll have to do some benchmarking. The best algorithm will depend on the distribution of your inputs.
Your algorithm may be nearly optimal, but you might want to do a quick check to rule out some possibilities before calling your square root routine. For example...
What are the differences between delegates and events?
...echnically a public Delegate variable would be exposing "data", but to the best of my knowledge OOP never mentioned any concepts quite like a Delegate (it's neither an "object" nor a "message"), and .NET really barely treats delegates like data anyway.
– jrh
A...