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Rolling or sliding window iterator?
...stige
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answered Jul 25 '11 at 21:47
Daniel DiPaoloDaniel DiPaolo
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Whether a variable is undefined [duplicate]
...ottyUCSD
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In R, how to get an object's name after it is sent to a function?
...parse-substitute trick:
a<-data.frame(x=1:10,y=1:10)
test<-function(z){
mean.x<-mean(z$x)
nm <-deparse(substitute(z))
print(nm)
return(mean.x)}
test(a)
#[1] "a" ... this is the side-effect of the print() call
# ... you could have done something useful with that ...
Why does (1 in [1,0] == True) evaluate to False?
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Test if string is a number in Ruby on Rails
...r
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answered Apr 14 '11 at 10:13
Jakob SJakob S
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PHP foreach loop key value
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How to parse/format dates with LocalDateTime? (Java 8)
...methods are available for all date/time related objects (e.g. LocalDate or ZonedDateTime)
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About Android image and asset sizes
... | 144 x 144 | 192 x 192
And these should display at roughly the same size on any device, provided you've placed these in density-specific folders (e.g. drawable-xhdpi, drawable-hdpi, etc.)
For reference, the pixel densities for these are:
ldpi | mdpi | tvdpi | hdpi | xhdpi | xxhdpi | xxx...
What's the difference between `1L` and `1`?
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typeof(x) # integer
y <- x+1
typeof(y) # double, twice the memory size
object.size(y) # 840 bytes (on win64)
z <- x+1L
typeof(z) # still integer
object.size(z) # 440 bytes (on win64)
...but also note that working excessively with integers can be dangerous:
1e9L * 2L # Works fine; fas...
How to clone a Date object?
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answered Jul 7 '09 at 7:24
Steve HarrisonSteve Harrison
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