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How can I get every nth item from a List?
...
}
and you write in a LINQish way
from var element in MyList.GetNth(10) select element;
2nd Edit:
To make it even more LINQish
from var i in Range(0, ((myList.Length-1)/n)+1) select list[n*i];
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Remove columns from dataframe where ALL values are NA
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dplyr now has a select_if verb that may be helpful here:
library(dplyr)
temp <- data.frame(x = 1:5, y = c(1,2,NA,4, 5), z = rep(NA, 5))
not_all_na <- function(x) any(!is.na(x))
not_any_na <- function(x) all(!is.na(x))
> temp
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The ALTER TABLE statement conflicted with the FOREIGN KEY constraint
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Here's a query to check the incorrect values: select distinct referrerTable.referenceColumn from referrerTable left join referredTable on referredTable.referenceColumn = referrerTable.referenceColumn where referredTable.referenceColum...
How to get a one-dimensional scalar array as a doctrine dql query result?
...as callback, instead of writing a closure.
$result = $em->createQuery("SELECT a.id FROM Auction a")->getScalarResult();
$ids = array_map('current', $result);
See Petr Sobotka's answer below for additional info regarding memory usage.
PHP >= 5.5
As jcbwlkr's answered below, the rec...
Where can I find the IIS logs?
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%SystemDrive%\inetpub\logs\LogFiles
Otherwise, check under IIS Manager, select the computer on the left pane, and in the middle pane, go under "Logging" in the IIS area. There you will se the default location for all sites (this is however overridable on all sites)
You could also look into
%Sy...
How to find the most recent file in a directory using .NET, and without looping?
...ry.GetFiles()
orderby f.LastWriteTime descending
select f).First();
// or...
var myFile = directory.GetFiles()
.OrderByDescending(f => f.LastWriteTime)
.First();
share...
How to use chrome web inspector to view hover code
...u can use Event Listener Breakpoints sidebar pane in the Scripts panel and select to pause in mouseover handlers.
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Making a UITableView scroll when text field is selected
... defaultCenter] addObserver:self
selector:@selector(keyboardWillShow:)
name:UIKeyboardWillShowNotification
object:nil];
// Register notification when the keyboard will b...
How to intercept click on link in UITextView?
...rtant:
Links in text views are interactive only if the text view is
selectable but noneditable. That is, if the value of the UITextView
the selectable property is YES and the isEditable property is NO.
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How to add text at the end of each line in Vim?
...e file, you can specify them in place of the %.
One way is to do a visual select and then type the :. It will fill in :'<,'> for you, then you type the rest of it (Notice you only need to add s/$/,/)
:'<,'>s/$/,/
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