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Unable to run app in Simulator: Xcode beta 6 iOS 8
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22 Answers
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How assignment works with Python list slice?
...two distinct operation that use very similar syntax:
1) slicing:
b = a[0:2]
This makes a copy of the slice of a and assigns it to b.
2) slice assignment:
a[0:2] = b
This replaces the slice of a with the contents of b.
Although the syntax is similar (I imagine by design!), these are two diff...
How to wait for 2 seconds?
...esn't explicitly lay out the required string format.
This will wait for 2 seconds:
WAITFOR DELAY '00:00:02';
The format is hh:mi:ss.mmm.
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sed: print only matching group
... replaced with the contents of the group
echo "foo bar <foo> bla 1 2 3.4" |
sed -n 's/.*\([0-9][0-9]*[\ \t][0-9.]*[ \t]*$\)/\1/p'
2 3.4
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C# equivalent to Java's charAt()?
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201
You can index into a string in C# like an array, and you get the character at that index.
Exa...
Single Line Nested For Loops
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172
The best source of information is the official Python tutorial on list comprehensions. List com...
PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)
... $item is still a reference to some value which is also being used by $arr[2]. So each foreach call in the second loop, which does not call by reference, replaces that value, and thus $arr[2], with the new value.
So loop 1, the value and $arr[2] become $arr[0], which is 'foo'.
Loop 2, the value and ...
Convert a row of a data frame to vector
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answered Jan 23 '13 at 16:42
Ben BolkerBen Bolker
160k1919 gold badges286286 silver badges366366 bronze badges
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LINQ where vs takewhile
... and find all elements matching the condition
var intList = new int[] { 1, 2, 3, 4, 5, -1, -2 };
Console.WriteLine("Where");
foreach (var i in intList.Where(x => x <= 3))
Console.WriteLine(i);
Console.WriteLine("TakeWhile");
foreach (var i in intList.TakeWhile(x => x <= 3))
Conso...