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What is the __del__ method, How to call it?
...is used, probably not like that: obj1.del() . So, my questions is how to call the __del__ method?
5 Answers
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How to select a single field for all documents in a MongoDB collection?
... include several fields. In the following operation, find() method returns all documents that match the query. In the result set, only the item and qty fields and, by default, the _id field return in the matching documents.
db.inventory.find( { type: 'food' }, { item: 1, qty: 1 } )
In this example ...
Understanding the meaning of the term and the concept - RAII (Resource Acquisition is Initialization
...e same way in C# by replacing synchronized with lock):
void foo()
{
// etc.
synchronized(someObject)
{
// if something throws here, the lock on someObject will
// be unlocked
}
// etc.
}
... is already using RAII: The mutex acquisition is done in the keyword (synchron...
SSL_connect returned=1 errno=0 state=SSLv3 read server certificate B: certificate verify failed
... that is trying to verify the SSL certification: SSL_CERT_FILE=/opt/local/etc/certs/cacert.pem rails generate jquery:install. In your case, you want to either set this as an environment variable somewhere the server picks it up or add something like ENV['SSL_CERT_FILE'] = /path/to/your/new/cacert.p...
Eclipse HotKey: how to switch between tabs?
...ately this means that I'm SOL if I nav into a non-Java file (JSP, XML, JS, etc.).
The fix for this is to "copy command" for this pair, and select all the "whens" that I want.
So far it's at least working beautifully for Java and JSP files.
This is a major PITA to set up, but it's just a one-ti...
How does Python's super() work with multiple inheritance?
...ave trouble
understanding the super() function (new style classes) especially when it comes to multiple inheritance.
16 A...
Why does += behave unexpectedly on lists?
...
The general answer is that += tries to call the __iadd__ special method, and if that isn't available it tries to use __add__ instead. So the issue is with the difference between these special methods.
The __iadd__ special method is for an in-place addition, that i...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
...ic unit of storage is analogous to JSON, Python dictionaries, Ruby hashes, etc. This is a rich data structure capable of holding arrays and other documents. This means you can often represent in a single entity a construct that would require several tables to properly represent in a relational db. T...
Referring to a file relative to executing script
...s: cd "${BASH_SOURCE%/*}" || exit, or read somevar < "${BASH_SOURCE%/*}/etc/somefile", Link Strongly Discourages $0 "Nothing that reads $0 will ever be bulletproof, because $0 itself is unreliable."
– ThorSummoner
Sep 29 '15 at 23:47
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Relationship between SciPy and NumPy
SciPy appears to provide most (but not all [1]) of NumPy's functions in its own namespace. In other words, if there's a function named numpy.foo , there's almost certainly a scipy.foo . Most of the time, the two appear to be exactly the same, oftentimes even pointing to the same function object.
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