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Tricks to manage the available memory in an R session
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I make aggressive use of the subset parameter with selection of only the required variables when passing dataframes to the data= argument of regression functions. It does result in some errors if I forget to add variables to both the formula and the select= vector, but it sti...
How do you track record relations in NoSQL?
...(A .NET based NoSQL Database with SQL support) your queries will be like
SELECT * FROM Comments WHERE userid = ‘That user’;
SELECT * FROM Comments WHERE pageid = ‘That user’;
SELECT * FROM Comments WHERE post-time > DateTime('2016, 1, 1');
SELECT * FROM Page WHERE tag = 'kendo'
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OrderBy descending in Lambda expression?
... orderby person.Name descending, person.Age descending
select person.Name;
is equivalent to:
var query = people.OrderByDescending(person => person.Name)
.ThenByDescending(person => person.Age)
.Select(person => person.Name);
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What's the $unwind operator in MongoDB?
...oDB employs an "NoSQL" approach to data storage, so perish the thoughts of selects, joins, etc. from your mind. The way that it stores your data is in the form of documents and collections, which allows for a dynamic means of adding and obtaining the data from your storage locations.
That being sai...
The breakpoint will not currently be hit. No symbols have been loaded for this document in a Silverl
...on --> Properties
Look under Common Properties --> Startup Project
Select multiple startup projects
select Start action on the projects you need to debug.
share
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In Xcode, how to suppress all warnings in specific source files?
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Select your target and show Build Phases. Then enter the name of the file in the search box, and you should see it listed in the Compile Sources phase. Double-click in the Compiler Flags column for that file and enter -w to t...
Resharper- Find all unused classes
... find unused references of a single file by right clicking on the file and selecting the "Find Usages" option. Is there any way I can see or get the list of all the unused classes or files in my project ?
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Jump to function definition in vim
... mentioned you have to use ctags.
You could also consider using plugins to select appropriate one or to preview the definition of the function under cursor.
Without plugins you will have a headache trying to select one of the hundreds overloaded 'doAction' methods as built in ctags support doesn't ...
iOS 7 - How to display a date picker in place in a table view?
...hose values.
As a delegate to this table, the sample uses the method "didSelectRowAtIndexPath" to open the UIDatePicker control.
For iOS 6.x and earlier, UIViewAnimation is used for sliding the UIDatePicker up on-screen and down off-screen. For iOS 7.x, the UIDatePicker is added in-line to th...
Hidden features of Perl?
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One of my favourite features in Perl is using the boolean || operator to select between a set of choices.
$x = $a || $b;
# $x = $a, if $a is true.
# $x = $b, otherwise
This means one can write:
$x = $a || $b || $c || 0;
to take the first true value from $a, $b, and $c, or a default of 0...