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Retrieve only the queried element in an object array in MongoDB collection
...r to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// Get just the docs that contain a shapes element where color is 'red'
{$match: {'shapes.color': 'red'}},
{$project: {
shapes: {$filter: {
...
How to center text vertically with a large font-awesome icon?
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I use icons next to text 99% of the time so I made the change globally:
.fa-2x {
vertical-align: middle;
}
Add 3x, 4x, etc to the same definition as needed.
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Why is parenthesis in print voluntary in Python 2.7?
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In Python 2.x print is actually a special statement and not a function*.
This is also why it can't be used like: lambda x: print x
Note that (expr) does not create a Tuple (it results in expr), but , does. This likely results in the confusion between...
Abstraction VS Information Hiding VS Encapsulation
...ften achieved through information hiding, which
is the process of hiding all of the secrets of object that do not
contribute to its essential characteristics.
In other words: abstraction = the object externally; encapsulation (achieved through information hiding) = the object internally,
Exam...
knitr Markdown highlighting in Emacs?
...r the former you need polymode and for the latter markdown.el. Besides, if all you want is to just switch the ESS engine from Sweave to knitr (without highlighting!), there is no need to go through all the complication of this article, just add (setq ess-swv-processor 'knitr) in you init file.
...
Adjust width and height of iframe to fit with content in it
...'iFrame1' );
resizeIFrameToFitContent( iFrame );
// or, to resize all iframes:
var iframes = document.querySelectorAll("iframe");
for( var i = 0; i < iframes.length; i++) {
resizeIFrameToFitContent( iframes[i] );
}
} );
</script>
<iframe src="usagelogs/defa...
Is there a working C++ refactoring tool? [closed]
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Unfortunately, Refactor for C++ doesn't work well (if at all) with large codebases.
– Daniel Rose
May 4 '11 at 9:46
1
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Reading CSV files using C#
...sualBasic but it works in C# just as well - remember that at the end it is all just IL)
use the Microsoft.VisualBasic.FileIO.TextFieldParser class to parse CSV file
Here is the sample code:
using (TextFieldParser parser = new TextFieldParser(@"c:\temp\test.csv"))
{
parser.TextFieldType = Fiel...
Convert column classes in data.table
...hat is the idiomatic way of doing this for a subset of columns (instead of all of them)? I've defined a character vector convcols of columns. dt[,lapply(.SD,as.numeric),.SDcols=convcols] is almost instant while dt[,convcols:=lapply(.SD,as.numeric),.SDcols=convcols] almost freezes up R, so I'm guessi...
:not(:empty) CSS selector is not working?
...idered empty by the HTML definition of "empty", since the content model of all void elements is always empty. So they will always match the :empty pseudo-class, whether or not they have a value. This is also why their value is represented by an attribute in the start tag, rather than text content wi...