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Adding placeholder text to textbox
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How do I combine two data frames?
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Yes, that's possible, see: stackoverflow.com/a/46661368/5717580
– martin-martin
Oct 10 '17 at 7:55
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How to sum a variable by group
...e(cbind(x$Frequency, x$Metric2, x$Metric3) ...
(embedding @thelatemail comment), aggregate has a formula interface too
aggregate(Frequency ~ Category, x, sum)
Or if you want to aggregate multiple columns, you could use the . notation (works for one column too)
aggregate(. ~ Category, x, sum)...
Multiline strings in JSON
...at you think your are. Maybe this answer explains it better: stackoverflow.com/a/9295597/359996. Note especially the bit about double escaping.
– user359996
Mar 7 '14 at 17:28
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Java Hashmap: How to get key from value?
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If you choose to use the Commons Collections library instead of the standard Java Collections API, you can achieve this with ease.
The BidiMap interface in the Collections library is a bi-directional map, allowing you to map a key to a value (like n...
What is
..., the ? must be Integer,Double, Short etc
– jbailie1991
Feb 27 '18 at 14:27
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Why shouldn't `'` be used to escape single quotes?
...s, you can use
html | numeric | hex
‘ | ‘ | ‘ // for the left/beginning single-quote and
’ | ’ | ’ // for the right/ending single-quote
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How to change the commit author for one specific commit?
I want to change the author of one specific commit in the history. It's not the last commit.
19 Answers
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Fastest Way of Inserting in Entity Framework
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To your remark in the comments to your question:
"...SavingChanges (for each
record)..."
That's the worst thing you can do! Calling SaveChanges() for each record slows bulk inserts extremely down. I would do a few simple tests which will v...
String length in bytes in JavaScript
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There is no way to do it in JavaScript natively. (See Riccardo Galli's answer for a modern appr...