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How to print last two columns using awk
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You can make use of variable NF which is set to the total number of fields in the input record:
awk '{print $(NF-1),"\t",$NF}' file
this assumes that you have at least 2 fields.
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Remove NA values from a vector
...cluding sum(), mean(), etc.)
Setting na.rm=TRUE does just what you're asking for:
d <- c(1, 100, NA, 10)
max(d, na.rm=TRUE)
If you do want to remove all of the NAs, use this idiom instead:
d <- d[!is.na(d)]
A final note: Other functions (e.g. table(), lm(), and sort()) have NA-related...
Programmatically trigger “select file” dialog box
...Is it possible to trigger its select file dialog box from a button's click event?
13 Answers
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How to compute the sum and average of elements in an array?
...d Apr 28 '12 at 1:54
Marcus RecckMarcus Recck
4,76322 gold badges1313 silver badges2626 bronze badges
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Use of #pragma in C
...m-specific, i.e. it tells the compiler to do something, set some option, take some action, override some default, etc. that may or may not apply to all machines and operating systems.
See msdn for more info.
share
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Ubuntu, vim, and the solarized color palette
I'd really like to get in on all the colorful goodness of the solarized colorscheme , but I can't seem to get it configured just right.
I have the main solarized file in my .vim/colors folder, I've set my terminal profile colors to what is listed on the site, and I've added the lines
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Get Android Device Name [duplicate]
...via HTC Sync the software is displaying the Name 'HTC Smith' . I would like to fetch this name via code.
12 Answers
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How can a Java program get its own process ID?
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There exists no platform-independent way that can be guaranteed to work in all jvm implementations.
ManagementFactory.getRuntimeMXBean().getName() looks like the best (closest) solution, and typically includes the PID. It's short, and probably works in every implementation in wide use.
On linux...
List comprehension in Ruby
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If you really want to, you can create an Array#comprehend method like this:
class Array
def comprehend(&block)
return self if block.nil?
self.collect(&block).compact
end
end
some_array = [1, 2, 3, 4, 5, 6]
new_array = some_array.comprehend {|x| x * 3 if x % 2 == 0}
puts...
Couldn't register with the bootstrap Server
... able to recover from this by unplugging the iPad, powering it down and back up, clearing all XCode caches and targets, and doing a clean build.
I'm running XCode 3.5.4 and iOS 4.2.1
Hope this helps someone.
-Mike
UPDATE:
Same problem running Xcode 4.3 and iOS5 - just power-cycle the device.
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