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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.
...
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
...
Pushing from local repository to GitHub hosted remote
...n my dev machine. I then created a remote repository in my GitHub account. Now, I am looking for how to push my local repository to the remote repository.
...
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
...
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...
Scheduling R Script
...
Now there is built in option in RStudio to do this, to run scheduler first install below packages
install.packages('data.table')
install.packages('knitr')
install.packages('miniUI')
install.packages('shiny')
insta...
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.
...
When to use an interface instead of an abstract class and vice versa?
...hod" is that it's nearly always somewhat re-entrant - the "derived" class knows about not just the "abstract" method of its base class that it is implementing, but also about the public methods of the base class, even though most times it does not need to call them.
(Overly simplified) example:
ab...
Cross-browser testing: All major browsers on ONE machine
...f using Sandboxie to run IE7 and IE8 in the same VM, thanks for the guide! Now I don't have to run three separate VMs just to test in IE6-IE8.
– Phil
Jan 8 '13 at 3:56
...
Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...
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
...