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Why is `[` better than `subset`?
...eval(expr, envir, enclos) : object 'cyl' not found
because R no longer "knows" where to find the object called 'cyl'. He also points out the truly bizarre stuff that can happen if by chance there is an object called 'cyl' in the global environment:
cyl <- 4
subscramble(mtcars, cyl == 4)
cyl &...
What are the effects of exceptions on performance in Java?
... class is loaded by the VM) and it makes throw not quite as slow. I don't know which JVM uses this new, better technique...
...but are you writing in Java so your code later on only runs on one JVM on one specific system? Since if it may ever run on any other platform or any other JVM version (pos...
How to set a bitmap from resource
... R.drawable.android_logo
);
Now you can use this bitmap object, whether you want to store it, or to use it in google maps while drawing a pic on fixed latitude and longitude, or to use some where else
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How to find the width of a div using vanilla JavaScript?
...
That, or cientWidth, altho I don't know the real difference.
– JCOC611
Jan 24 '11 at 21:51
127
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Is mongodb running?
... quickly checking if mongodb is running, this quick nc trick will let you know.
nc -zvv localhost 27017
The above command assumes that you are running it on the default port on localhost.
For auto-starting it, you might want to look at this thread.
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How do I export UIImage array as a movie?
...erious problem: I have an NSArray with several UIImage objects. What I now want to do, is create movie from those UIImages . But I don't have any idea how to do so.
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Inheriting class methods from modules / mixins in Ruby
It is known that in Ruby, class methods get inherited:
4 Answers
4
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Difference between variable declaration syntaxes in Javascript (including global variables)?
...undefined.
This only applies to the window object, and only (as far as I know) to IE8 and earlier (or IE9-IE11 in the broken "compatibility" mode). Other browsers are fine with deleting window properties, subject to the rules above.
When var happens
The variables defined via the var statement a...
Create, read, and erase cookies with jQuery [duplicate]
...ileNotFound" (or something close to that, I'm not at my dev computer right now). Thanks!
– jackerman09
Sep 27 '13 at 18:24
8
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How to replace a string in a SQL Server Table Column
...ave a table ( SQL Sever ) which references paths ( UNC or otherwise), but now the path is going to change.
10 Answers
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