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image.onload event and browser cache
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edited May 23 '17 at 11:47
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answered Sep 10 '12 at 15:41
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Postgres: Distinct but only for one column
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answered Jun 4 '13 at 12:36
Clodoaldo NetoClodoaldo Neto
91.2...
What is & used for
...inQuentin
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JS: Check if date is less than 1 hour ago?
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Krishna NKrishna N
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Making text background transparent but not text itself
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James CoyleJames Coyle
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How to copy an object in Objective-C
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Adam WrightAdam Wright
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How to revert a Git Submodule pointer to the commit stored in the containing repository?
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answered Oct 24 '11 at 23:28
Brian RiehmanBrian Riehman
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Pass a data.frame column name to a function
...ou can just use the column name directly:
df <- data.frame(A=1:10, B=2:11, C=3:12)
fun1 <- function(x, column){
max(x[,column])
}
fun1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x...
Programmatically Hide/Show Android Soft Keyboard [duplicate]
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answered Sep 1 '11 at 0:32
DaveDave
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What does a b prefix before a python string mean?
...rs with values in the 0-255 range, like a list:
bytes([72, 101, 108, 108, 111])
and indexing gives you back the integers (but slicing produces a new bytes value; for the above example, value[0] gives you 72, but value[:1] is b'H' as 72 is the ASCII code point for the capital letter H).
bytes mod...