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Changing column names of a data frame
... Thank you. I think this is somehow annoying with R: Why is it so difficult to change the column name if you do not want to use the index number but the old name :(
– Arne
Mar 18 '14 at 14:41
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What is the difference between double-ampersand (&&) and semicolon (;) in Linux Bash?
What is the difference between ampersand and semicolon in Linux Bash ?
3 Answers
3
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What happens if a Android Service is started multiple times?
If I have the following code:
4 Answers
4
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How does HashSet compare elements for equality?
...qualityComparer<T> (EqualityComparer<T>.Default unless you specify a different one on construction).
When you add an element to the set, it will find the hash code using IEqualityComparer<T>.GetHashCode, and store both the hash code and the element (after checking whether the elem...
select * vs select column
If I just need 2/3 columns and I query SELECT * instead of providing those columns in select query, is there any performance degradation regarding more/less I/O or memory?
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How can I break an outer loop with PHP?
...g just a break-n statement:
foreach(...)
{
foreach(...)
{
if (i.name == j)
break 2; //Breaks 2 levels, so breaks outermost foreach
}
}
If you're in php >= 5.3, you can use labels and gotos, similar as in ActionScript:
foreach (...)
{
foreach (...)
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Array.Copy vs Buffer.BlockCopy
...time when you are copying primitive type arrays, or should you only use it if you're coding for performance? Is there anything inherently dangerous about using Buffer.BlockCopy over Array.Copy ?
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How to scroll to the bottom of a UITableView on the iPhone before the view appears
... that we need to call this before reloading the tableview... It won't work if we write this after [table reloadData];
– Fahim Parkar
Jan 14 '15 at 5:42
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Toggle button using two image on different state
... Add two images(selected/unselected) in check.xml which will work as two different states of toggle button
– AkashG
Jul 16 '12 at 7:13
19
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LINQ OrderBy versus ThenBy
Can anyone explain what the difference is between:
4 Answers
4
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