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Retrieve only the queried element in an object array in MongoDB collection
...d({"shapes.color": "red"}, {_id: 0, 'shapes.$': 1});
MongoDB 3.2 Update
Starting with the 3.2 release, you can use the new $filter aggregation operator to filter an array during projection, which has the benefit of including all matches, instead of just the first one.
db.test.aggregate([
// ...
How do I make a list of data frames?
... don't wait until you have a bunch of a data.frames to add them to a list. Start with the list.
The rest of the this answer will cover some common cases where you might be tempted to create sequential variables, and show you how to go straight to lists. If you're new to lists in R, you might want t...
Error during installing HAXM, VT-X not working
...I downloaded appropriate file HAXM file for Windows 7 64 bit, unpacked and started installing. However, during the installation process I get this error:
...
How can I specify a local gem in my Gemfile?
...th to config/spring.rb seems to help pickup your local gem changes after restarting rails console/server.
– Jason R
Sep 10 '16 at 18:52
5
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:not(:empty) CSS selector is not working?
... value. This is also why their value is represented by an attribute in the start tag, rather than text content within start and end tags.
Also, from the Selectors spec:
The :empty pseudo-class represents an element that has no children at all. In terms of the document tree, only element nodes a...
What is in your Mathematica tool bag? [closed]
... @belisarius, I hadn't read the history, that's funny. I've just started using Wannier90, but it is some of the best organized and well written Fortran code I've seen. Makes me almost consider using Fortran ...
– rcollyer
Nov 19 '10 at 14:46
...
Is it .yaml or .yml?
...-quote Albert Einstein).
Instead, notice that, in general, few extensions start with "Y". Commonly, on the other hand, the letter X is used for a great variety of meanings including "cross," "extensible," "extreme," "variable," etc. (e.g. in XML). So starting with "Y" already conveys much informati...
Proper way to make HTML nested list?
...t. It is useful for things like tables of contents, such as the one at the start of this article:
Chapter One
Section One
Section Two
Section Three
Chapter Two
Chapter Three
The key to nesting lists is to remember that the nested list should relate to one specific list...
Make anchor link go some pixels above where it's linked to
... 100);
}
}
// Captures click events of all <a> elements with href starting with #
$(document).on('click', 'a[href^="#"]', function(event) {
// Click events are captured before hashchanges. Timeout
// causes offsetAnchor to be called after the page jump.
window.setTimeout(function() {
...
android studio 0.4.2: Gradle project sync failed error
...my own question....
This worked for me.
File -> Invalidate caches / Restart
Shutdown Android Studio
Rename/remove .gradle folder in the user home directory
Restart Android Studio let it download all the Gradle stuff it needs
Gradle build success !
Rebuild project.... success !
Out of curiousi...