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How to validate an email address using a regular expression?
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Android Camera Preview Stretched
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edited Feb 8 '16 at 14:57
Anirudh Sharma
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data.table vs dplyr: can one do something well the other can't or does poorly?
... x y z
# 1: 1 a 1
# 2: 1 a 2
# 3: 1 b 3
# 4: 1 b 4
# 5: 2 a 5
# 6: 2 a 6
# 7: 2 b 7
# 8: 2 b 8
DT2 = data.table(x=1:2, y=c("a", "b"), mul=4:3, key=c("x", "y"))
# x y mul
# 1: 1 a 4
# 2: 2 b 3
And you would like to get sum(z) * mul for each row in DT2 while joining by columns x,y. We can eit...
How to use NULL or empty string in SQL
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answered Mar 27 '13 at 15:55
codingbadgercodingbadger
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Using std Namespace
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edited Nov 30 '16 at 17:11
Augustin
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answered Aug 12 '09 at...
ASP.NET MVC 3: Override “name” attribute with TextBoxFor
...ghtmare.....
– James McCormack
Mar 17 '14 at 18:31
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How could I convert data from string to long in c#
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187
This answer no longer works, and I cannot come up with anything better then the other answers (s...
Fluent Validation vs. Data Annotations [closed]
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edited May 7 '18 at 15:33
gpaoli
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answered Jul 2...
Why should text files end with a newline?
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Iulian Onofrei
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answered Apr 8 '09 at 12:46
Konrad RudolphKonra...