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Why would you use an ivar?
...in order to do the right thing.
Binary Size
Declaring everything readwrite by default usually results in many accessor methods you never need, when you consider your program's execution for a moment. So it will add some fat to your program and load times as well.
Minimizes Complexity
In some cases, ...
Flask-SQLalchemy update a row's information
...tself. Then, db.session.commit().
For example:
admin = User.query.filter_by(username='admin').first()
admin.email = 'my_new_email@example.com'
db.session.commit()
user = User.query.get(5)
user.name = 'New Name'
db.session.commit()
Flask-SQLAlchemy is based on SQLAlchemy, so be sure to check out...
How do I get the Git commit count?
...l approach given in the original question) and incorrect: you can see this by inverting the match (git shortlog | grep -Ev '^[ ]+\w+') and seeing that e.g. commits with no message (i.e., "<none>") are not counted. Using git rev-list HEAD --count is both more succinct and more accurate.
...
What do we mean by Byte array? [closed]
...
A byte is 8 bits (binary data).
A byte array is an array of bytes (tautology FTW!).
You could use a byte array to store a collection of binary data, for example, the contents of a file. The downside to this is that the entire...
what is the difference between a portlet and a servlet?
... components which use Java for
their implementation.
Portlets are managed by a portlet container just like servlet is
managed by servlet container.
Both static and dynamic content can be generated by Portlets and
Servlets.
The life cycle of portlets and servlets is controlled by the container
Th...
How do disable paging by swiping with finger in ViewPager but still be able to swipe programmaticall
I have ViewPager and below it I have 10 buttons. By clicking on button, for example #4, the pager goes immediately to page #4 by mPager.setCurrentItem(3); . But, I want to disable the paging by swiping with finger horizontally. Thus, the paging is done ONLY by clicking on the buttons.
So, how I ...
Drop data frame columns by name
...
Or, alternatively, you can make a list of those to keep and refer to them by name :
keeps <- c("y", "a")
DF[keeps]
EDIT :
For those still not acquainted with the drop argument of the indexing function, if you want to keep one column as a data frame, you do:
keeps <- "y"
DF[ , keeps, drop ...
What exactly is a reentrant function?
...m;
void foo(callback f)
{
m.lock();
// use the resource protected by the mutex
if (f) {
f();
}
// use the resource protected by the mutex
m.unlock();
}
Another function could well need to lock the same mutex:
void bar()
{
foo(nullptr);
}
At first sight, ev...
How does one write code that best utilizes the CPU cache to improve performance?
...s
Organize your data to avoid alignment holes (sorting your struct members by decreasing size is one way)
Beware of the standard dynamic memory allocator, which may introduce holes and spread your data around in memory as it warms up.
Make sure all adjacent data is actually used in the hot loops. Ot...
How to Sort Multi-dimensional Array by Value?
How can I sort this array by the value of the "order" key? Even though the values are currently sequential, they will not always be.
...