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What's the difference between :: (double colon) and -> (arrow) in PHP?
... used to access static members, such usage is discouraged), while :: is usually used to access static members (though in a few special cases, it's used to access instance members).
In general, :: is used for scope resolution, and it may have either a class name, parent, self, or (in PHP 5.3) static...
Django - filtering on foreign key properties
...
You can add a .query.as_sql() to see what sql will actually be executed.
– fastmultiplication
Jul 17 '10 at 5:19
...
SQLAlchemy IN clause
...w about
session.query(MyUserClass).filter(MyUserClass.id.in_((123,456))).all()
edit: Without the ORM, it would be
session.execute(
select(
[MyUserTable.c.id, MyUserTable.c.name],
MyUserTable.c.id.in_((123, 456))
)
).fetchall()
select() takes two parameters, the first...
Assigning a variable NaN in python without numpy
...aking) be said to be equal to one another -- see What is the rationale for all comparisons returning false for IEEE754 NaN values? for more details and information.
Instead, use math.isnan(...) if you need to determine if a value is NaN or not.
Furthermore, the exact semantics of the == operation...
In Intellij, how do I toggle between camel case and underscore spaced?
...
I use a plugin called String Manipulation which has the capabilities you're looking for (and more).
Select historyOfPresentIllness and press Alt+M to bring up the plugin menu, then press:
5 - To snake_case (or to camelCase) which convert...
Replacing some characters in a string with another character
I have a string like AxxBCyyyDEFzzLMN and I want to replace all the occurrences of x , y , and z with _ .
5 Answers
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cancelling a handler.postdelayed process
...nnable, SPLASH_DISPLAY_LENGTH);
And this to remove it: myHandler.removeCallbacks(myRunnable);
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How do I catch a numpy warning like it's an exception (not just for testing)?
...ng: divide by zero encountered in divide
array([0])
>>> np.seterr(all='print')
{'over': 'warn', 'divide': 'warn', 'invalid': 'warn', 'under': 'ignore'}
>>> np.array([1])/0 #'print' mode
Warning: divide by zero encountered in divide
array([0])
This means that the warning you see...
What's the $unwind operator in MongoDB?
...hat 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 said, in order to understand the concept behind the $unwind parameter, you first must understand what the use case that you ...
What is the JSF resource library for and how should it be used?
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Actually, all of those examples on the web wherein the common content/file type like "js", "css", "img", etc is been used as library name are misleading.
Real world examples
To start, let's look at how existing JSF implementati...