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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...
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.
...
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...
How do you use script variables in psql?
...
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).
...
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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How exactly does a generator comprehension work?
...
Do you understand list comprehensions? If so, a generator expression is like a list comprehension, but instead of finding all the items you're interested and packing them into list, it waits, and yields each item out of the expression, one...
Is there a C# case insensitive equals operator?
...ensitive comparison, use this method. If you just want to make sure "FILE" and "file" are both accepted, use "OrdinalIgnoreCase" or your code might not work in places like Turkish locales. For more info, see moserware.com/2008/02/does-your-code-pass-turkey-test.html
– Jeff Mose...
Extreme wait-time when taking a SQL Server database offline
...e restore from live backup) on my dev database, but the 'Take Offline' command via SQL Server Management Studio is performing extremely slowly - on the order of 30 minutes plus now. I am just about at my wits end and I can't seem to find any references online as to what might be causing the speed ...
How to get the user input in Java?
...stem.in);
String s = scan.next();
int i = scan.nextInt();
BufferedReader and InputStreamReader classes
import java.io.BufferedReader;
import java.io.InputStreamReader;
//...
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String s = br.readLine();
int i = Integer.parseInt...