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What's the $unwind operator in MongoDB?
...g and obtaining the data from your storage locations.
That being said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you are trying to quote is saying. The example document from mongodb.org is as follows:
{
title : "this is my ti...
How do you detect where two line segments intersect? [closed]
...Specifically, h is how much you have to multiply the length of the line in order to exactly touch the other line.
Therefore, If h<0, it means the rectangle line is "behind" the given line (with "direction" being "from A to B"), and if h>1 the rectangle line is "in front" of the given line.
D...
How can I specify a local gem in my Gemfile?
...
In order to use local gem repository in a Rails project, follow the steps below:
Check if your gem folder is a git repository (the command is executed in the gem folder)
git rev-parse --is-inside-work-tree
Getting repository...
What are the differences between a HashMap and a Hashtable in Java?
...es is LinkedHashMap, so in the event that you'd want predictable iteration order (which is insertion order by default), you could easily swap out the HashMap for a LinkedHashMap. This wouldn't be as easy if you were using Hashtable.
Since synchronization is not an issue for you, I'd recommend Has...
What are naming conventions for MongoDB?
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Naming convention for collection
In order to name a collection few precautions to be taken :
A collection with empty string (“”) is not a valid collection name.
A collection name should not contain the null character because this defines the end of collect...
Quickly reading very large tables as dataframes
...e end object is a data frame. So you have to convert it to a zoo object in order to use it with zoo. Look at the examples in the zoo docs for illustrations.
– JD Long
Apr 2 '13 at 12:48
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Is it possible to view RabbitMQ message contents directly from the command line?
...RabbitMQ queue to local files and requeuing the messages in their original order.
Example usage (to dump the first 50 messages of queue incoming_1):
rabbitmq-dump-queue -url="amqp://user:password@rabbitmq.example.com:5672/" -queue=incoming_1 -max-messages=50 -output-dir=/tmp
...
Convert Elixir string to integer or float
...ust be the string representation of a float including a decimal point. In order to parse a string without decimal point as a float then Float.parse/1 should be used. Otherwise, an ArgumentError will be raised.
But Float.parse returns a tuple of 2 elements, not the number you want, so put it into p...
Forward declaration of a typedef in C++
...orward declaration can be made if we only need to know the type exists, in order to create pointers or references to the type. Since the OP didn't show code, but complained it wouldn't compile, I assumed (probably correctly) that the OP was trying to use the type, not just refer to it.
...
Favorite (G)Vim plugins/scripts? [closed]
... Link to all his vim contributions: vim.org/account/profile.php?user_id=9012
– Benjamin Oakes
May 27 '10 at 0:11
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