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The Android emulator is not starting, showing “invalid command-line parameter”
... simple "Hello World" program in Eclipse . I added nothing to a Java file and only added a text view in file main.xml as
...
lsof survival guide [closed]
lsof is an increadibly powerful command-line utility for unix systems. It lists open files, displaying information about them. And since most everything is a file on unix systems, lsof can give sysadmins a ton of useful diagnostic data.
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What does a lazy val do?
...3
In contrast to a method (defined with def) a lazy val is executed once and then never again. This can be useful when an operation takes long time to complete and when it is not sure if it is later used.
scala> class X { val x = { Thread.sleep(2000); 15 } }
defined class X
scala> class Y ...
Named regular expression group “(?Pregexp)”: what does “P” stand for?
...major" version, Python 1.5, by the end of
this year. I hope that Python and Perl can co-exist in years to come;
cross-pollination can be good for both languages. (I believe Larry
had a good look at Python when he added objects to Perl 5; O'Reilly
publishes books about both languages.)
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Does it make sense to do “try-finally” without “catch”?
... resources to be cleaned up appropriately. Below is a concrete example of handling the exception from a calling method.
public void yourOtherMethod() {
try {
yourMethod();
} catch (YourException ex) {
// handle exception
}
}
public void yourMethod() throws YourExcep...
How do you use script variables in psql?
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Postgres variables are created through the \set command, for example ...
\set myvariable value
... and can then be substituted, for example, as ...
SELECT * FROM :myvariable.table1;
... or ...
SELECT * FROM table1 WHERE :myvariable IS NULL;
edit: As of psql 9.1, varia...
Hide keyboard when scroll UITableView
...board when i start scrolling UITableView. I search about this in internet, and most answer is subclassing UITableView (http://stackoverflow.com/questions/3499810/tapping-a-uiscrollview-to-hide-the-keyboard).
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Python - 'ascii' codec can't decode byte
...u need to change the encoding, you need to decode it into a unicode string and then encode it as the desired encoding.
– Winston Ewert
Mar 12 '13 at 16:24
20
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Order data frame rows according to vector with specific order
...work as long as your target contains exactly the same elements as df$name, and neither contain duplicate values.
From ?match:
match returns a vector of the positions of (first) matches of its first argument
in its second.
Therefore match finds the row numbers that matches target's elements, and...
Python - Create a list with initial capacity
...i]= message
return result
Results. (evaluate each function 144 times and average the duration)
simple append 0.0102
pre-allocate 0.0098
Conclusion. It barely matters.
Premature optimization is the root of all evil.
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