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What does .SD stand for in data.table in R
...history of baseball
fkt = c('teamIDBR', 'teamIDlahman45', 'teamIDretro')
# confirm that they're stored as `character`
Teams[ , sapply(.SD, is.character), .SDcols = fkt]
# teamIDBR teamIDlahman45 teamIDretro
# TRUE TRUE TRUE
If you're confused by the use of sapply here,...
Why must we define both == and != in C#?
...eate the != operator? I can't know for sure unless someone from Microsoft confirms this, but this is what I can determine from reasoning on the facts.
To prevent unexpected behavior
Perhaps I want to do a value comparison on == to test equality. However, when it came to != I didn't care at all...
How is location accuracy measured in Android?
...but that seemed to be just a guess so I would really like to find a way to confirm if it's that or a 95% confidence circle or something else.
– John R.B. Palmer
Jun 16 '10 at 16:10
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Curious null-coalescing operator custom implicit conversion behaviour
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Now that I have the End User Preview of Roslyn, I can confirm that it's fixed there. (It's still present in the native C# 5 compiler though.)
– Jon Skeet
Apr 11 '14 at 9:59
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What happens if I define a 0-size array in C/C++?
... I understand. Since I am not too savvy on C terms of the art... could you confirm whether my reasoning seems correct ?
– Matthieu M.
Mar 15 '12 at 16:03
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Javascript: How to detect if browser window is scrolled to bottom?
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Confirmed working on FF, Chrome, IE10, Chrome for Android. Thank you @Dekel!
– Basj
Nov 2 '16 at 20:40
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Getting the IP address of the current machine using Java
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Works on Windows; can we confirm if OSX is still a problem?
– trilogy
Oct 2 '18 at 14:31
5
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Why CancellationToken is separate from CancellationTokenSource?
... design.
The accepted answer got the rationale exactly right. Here's the confirmation from the team who designed this feature (emphasis mine):
Two new types form the basis of the framework: A CancellationToken is
a struct that represents a ‘potential request for cancellation’. This
str...
How to apply a function to two columns of Pandas dataframe
...oach in thequestion: df['col_3'] = df[['col_1','col_2']].apply(f) just to confirm, the approach in the question didn't work because the poster did not specify this axis=1, the default is axis = 0?
– Lost1
Jul 19 '17 at 19:41
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String.equals versus == [duplicate]
...s the only thing they can say:
Using the residence alone, it's tough to confirm that it's the same Jorman. Since they're 2 different addresses, it's just natural to assume that those are 2 different persons.
That's how the operator == behaves. So it will say that datos[0]==usuario is false, beca...