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How do you delete a column by name in data.table?
...of the following will remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a -- A safe idiom for e...
Static classes and methods in coffeescript
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1 Answer
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Is there a method that calculates a factorial in Java?
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answered May 21 '09 at 1:45
Karl the PaganKarl the Pagan
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python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B
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12 Answers
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Do SVG docs support custom data- attributes?
...in XML attributes whose names start with data- such as <p data-myid="123456"> . Is this part of the SVG spec too?
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Extract substring in Bash
Given a filename in the form someletters_12345_moreleters.ext , I want to extract the 5 digits and put them into a variable.
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Pandas selecting by label sometimes return Series, sometimes returns DataFrame
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Granted that the behavior is inconsistent, but I think it's easy to imagine cases where this i...
Eclipse error: “The import XXX cannot be resolved”
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How to sort a list in Scala by two fields?
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rows.sortBy(r => (r.lastName, r.firstName))
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How to implement “select all” check box in HTML?
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316
<script language="JavaScript">
function toggle(source) {
checkboxes = document.getEleme...