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Only read selected columns
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Say the data are in file data.txt, you can use the colClasses argument of read.table() to skip...
Best way to parseDouble with comma as decimal separator?
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How can I get file extensions with JavaScript?
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Select mySQL based only on month and year
...n my mySQL DB that has some rows. One of this row is a DATE, like this: 2012-02-01
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Split comma-separated strings in a column into separate rows
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This old question frequently is being used as dupe target (tagged with r-faq). As of today, it h...
VBoxManage: error: Failed to create the host-only adapter
I am running vagrant 1.4 and virtual box 4.3 on fedora 17 machine. When I do "vagrant up", I get this error:
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What are all the uses of an underscore in Scala?
...K[_],T](a: K[T])
Ignored variables
val _ = 5
Ignored parameters
List(1, 2, 3) foreach { _ => println("Hi") }
Ignored names of self types
trait MySeq { _: Seq[_] => }
Wildcard patterns
Some(5) match { case Some(_) => println("Yes") }
Wildcard patterns in interpolations
"abc" m...
MYSQL import data from csv using LOAD DATA INFILE
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How to initialize a two-dimensional array in Python?
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for i in range (0, 10): \
new = [] \ can be replaced } this too
for j in range (0, 10): } with a list /
new.append(foo) / comprehension /
twod_li...
How to select multiple rows filled with constants?
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