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Combining INSERT INTO and WITH/CTE
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edited May 24 '12 at 11:38
answered Jul 22 '10 at 5:54
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Configuring IntelliJ IDEA for unit testing with JUnit
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answered Jan 21 '11 at 10:46
Igor KonoplyankoIgor Konoplyanko
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In Python, how do you convert seconds since epoch to a `datetime` object?
...datetime.datetime.fromtimestamp(1284286794)
datetime.datetime(2010, 9, 12, 11, 19, 54)
or
>>> datetime.datetime.utcfromtimestamp(1284286794)
datetime.datetime(2010, 9, 12, 10, 19, 54)
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Drop data frame columns by name
...st of names :
DF <- data.frame(
x=1:10,
y=10:1,
z=rep(5,10),
a=11:20
)
drops <- c("x","z")
DF[ , !(names(DF) %in% drops)]
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted wi...
How do I change the formatting of numbers on an axis with ggplot?
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answered Jul 23 '12 at 11:41
Jim M.Jim M.
5,26422 gold badges1818 silver badges3232 bronze badges
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Android Spinner: Get the selected item change event
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answered Nov 11 '09 at 10:50
znqznq
41.7k3838 gold badges113113 silver badges141141 bronze badges
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Using mixins vs components for code reuse in Facebook React
...93C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 45.2525 4.66231 44.6595 4.66231C43.6264 4.66231 43.1481 5.28821 43.1481 6.59048V11.9512C43.1481 13.2535 43.6264 13.8962 44.6595 13.8962C45.69...
What's in an Eclipse .classpath/.project file?
...le for example) ?
– Guy Avraham
Dec 11 '18 at 15:01
2
@GuyAvraham that depends on how you work wi...
How do I show a Save As dialog in WPF?
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answered Apr 11 '11 at 14:46
Aaron McIverAaron McIver
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How to disable code formatting for some part of the code using comments?
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Carlos FonsecaCarlos Fonseca
5,99111 gold badge1414 silver badges1313 bronze badges
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