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List comprehension rebinds names even after scope of comprehension. Is this right?
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Also note that now in 2.7, set and dictionary comprehensions (and generators) have private scopes, but list comprehensions still don't. While this makes some sense in that the former were all back-ported from Python 3, it really makes the c...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
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Update
data.table v1.9.6+ now supports OP's original attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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How to add to an existing hash in Ruby
...'
# This is then available immediately
hash[:b]
# => "Bee"
# The hash now contains both keys
hash
# => { :a => 'a', :b => 'Bee' }
Ruby on Rails confuses this somewhat by providing HashWithIndifferentAccess where it will convert freely between Symbol and String methods of addressing.
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Storing time-series data, relational or non?
...s to the disk space used.
You can get rid of it. Please.
Elevation
Now that you have removed the impediment, you may not have recognised it, but your table is in Sixth Normal Form. Very high speed, with just one Index on the PK. For understanding, read this answer from the What is Sixth Nor...
String concatenation: concat() vs “+” operator
...ring cat(String a, String b) {
a += b;
return a;
}
}
Now disassemble with javap -c (included in the Sun JDK). You should see a listing including:
java.lang.String cat(java.lang.String, java.lang.String);
Code:
0: new #2; //class java/lang/StringBuilder
3: dup
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What does glLoadIdentity() do in OpenGL?
... with all of the random functions that I have in my code. They work and I know when to use them, but I don't know why I need them or what they actually do.
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Concrete Javascript Regex for Accented Characters (Diacritics)
...and E, but I left them out because only historians seem interested in them now, and the D and E sets don't even render correctly in my browser.
The original regex stopping at \u017F borked on the name "Șenol". According to FontSpace's Unicode Analyzer, that first character is \u0218, LATIN CAPITAL...
how to check the dtype of a column in python pandas
...ent functions to treat numeric columns and string columns. What I am doing now is really dumb:
6 Answers
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Bootstrap dropdown sub menu missing
...Mark Otto..
"Submenus just don't have much of a place on the web right now, especially the mobile web. They will be removed with 3.0" - https://github.com/twbs/bootstrap/pull/6342
But, with a little extra CSS you can get the same functionality.
Bootstrap 4 (navbar submenu on hover)
.navbar-n...
How to avoid passing parameters everywhere in play2?
...>
}
</div>
@content
</body>
</html>
Now if you have templates calling this main template, you can have the menus parameter implicitly passed for you to the main template by the Scala compiler if it is declared as an implicit parameter in these templates as well...