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How to filter Pandas dataframe using 'in' and 'not in' like in SQL
How can I achieve the equivalents of SQL's IN and NOT IN ?
9 Answers
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CSS “and” and “or”
... Ok, thanks for light. I hate styling forms, but it's my task, and site isn't mine. I'll apply classes to inputs.
– Misiur
May 9 '10 at 9:02
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In Python, how does one catch warnings as if they were exceptions?
... warnings. I want to be able to use the try except syntax to properly handle these warnings. Is there a way to do this?
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Question mark and colon in JavaScript
...rm of: condition ? value-if-true : value-if-false
Think of the ? as "then" and : as "else".
Your code is equivalent to
if (max != 0)
hsb.s = 255 * delta / max;
else
hsb.s = 0;
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String.IsNullOrWhiteSpace in LINQ Expression
...NOT (([t0].[Diameter] IS NULL) OR (LTRIM(RTRIM([t0].[Diameter])) = @p0))
and for Linq to SQL almost but not quite the same
DECLARE @p0 NVarChar(1000) = ''
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WHERE NOT (LTRIM(RTRIM([t0].[TypeName])) = @p0)
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How to test if list element exists?
...es(foo) # TRUE
"b" %in% names(foo) # TRUE
"c" %in% names(foo) # FALSE
...and foo[["a"]] is safer than foo$a, since the latter uses partial matching and thus might also match a longer name:
x <- list(abc=4)
x$a # 4, since it partially matches abc
x[["a"]] # NULL, no match
[UPDATE] So, back t...
Dispelling the UIImage imageNamed: FUD
...Feb 2014: Note that this question dates from iOS 2.0! Image requirements and handling have moved on a lot since then. Retina makes images bigger and loading them slightly more complex. With the built in support for iPad and retina images, you should certainly use ImageNamed in your code .
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Using R to download zipped data file, extract, and import data
... of online csvs are zipped. Is there a way to download, unzip the archive, and load the data to a data.frame using R? #Rstats"
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Passing two command parameters using a WPF binding
I have a command which I am executing from my XAML file using the following standard syntax:
5 Answers
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Parallel.ForEach vs Task.Run and Task.WhenAll
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The first version will synchronously block the calling thread (and run some of the tasks on it).
If it's a UI thread, this will freeze the UI.
The second version will run the tasks asynchronously in the thread pool and release the calling thread until they're done.
There are also diffe...