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How to check if object has any properties in JavaScript?
...s a direct property, and not inherited from the object's prototype chain.
Edit
From the comments: You can put that code in a function, and make it return false as soon as it reaches the part where there is the comment
Performance Test
Test Of Object.Keys vs For..In When testing for any propertie...
How to allow to accept only image files?
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edited Jun 10 '17 at 7:35
mehulmpt
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Drop data frame columns by name
...e to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to keep one column as a data frame, you do:
keeps <- "y"
DF[ , keeps, drop = FALSE]
drop=TRUE (or not mentioning it) wil...
Android ImageView Zoom-in and Zoom-Out
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edited Jan 9 '14 at 10:39
Simulant
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How to check that an object is empty in PHP?
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edited Apr 5 at 1:24
answered Feb 23 '12 at 11:39
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How to list the tables in a SQLite database file that was opened with ATTACH?
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edited Apr 16 '14 at 15:05
Tuan
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Difference between Java Enumeration and Iterator
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edited Aug 29 at 5:04
SusanW
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Can I use the range operator with if statement in Swift?
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edited Aug 27 '17 at 7:30
Ahmad F
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“Warning: iPhone apps should include an armv6 architecture” even with build config set
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edited May 23 '17 at 12:34
Community♦
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answered Oct 7 '11 at...
Remove empty array elements
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edited Mar 10 at 3:20
answered Sep 6 '10 at 21:10
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