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What is scope/named_scope in rails?
...u marked those who receive a newsletter by adding a field to the Users Database (user.subscribed_to_newsletter = true). Naturally, you sometimes want to get those Users who are subscribed to your newsletter.
You could, of course, always do this:
User.where(subscribed_to_newsletter: true).each do #...
What exactly do the Vagrant commands do?
... and prepare boxes to use that.
Also some times, you may want to use ssh based automation with your VMs. In that case, knowing which key is being used is useful. You could do use normal ssh command - ssh -i keyfile ..
vagrant status <vmname>
This command is a wrapper which provides the info...
When is each sorting algorithm used? [closed]
...cant.
Insertion sort: When N is guaranteed to be small, including as the base case of a quick sort or merge sort. While this is O(N^2), it has a very small constant and is a stable sort.
Bubble sort, selection sort: When you're doing something quick and dirty and for some reason you can't just ...
How to convert a number to string and vice versa in C++
... = 0);
int stoi(const string& str, size_t *idx = 0, int base = 10);
long stol(const string& str, size_t *idx = 0, int base = 10);
unsigned long stoul(const string& str, size_t *idx = 0, int base = 10);
long long stoll(const string& str, size...
In what order are Panels the most efficient in terms of render time and performance?
... of the parent) results in horrible performance. I created a layout panel based on the Canvas which achieved my desired result with minimal work (I copied the source for the canvas and modified around 20 lines of it).
Available Panels:
Canvas
Defines an area within which you can explicitly ...
increase legend font size ggplot2
...
You can also specify the font size relative to the base_size included in themes such as theme_bw() (where base_size is 11) using the rel() function.
For example:
ggplot(mtcars, aes(disp, mpg, col=as.factor(cyl))) +
geom_point() +
theme_bw() +
theme(legend.text=element...
What are the drawbacks of Stackless Python? [closed]
...ython.
There are absolutely no plans for "significant changes to the code base". That quote and reference hyperlink from Arafangion's (see the comment) are from roughly 2000/2001. The structural changes have long been done, and it's what I mentioned above. Stackless as it is now is stable and matu...
Eager load polymorphic
...y guess is that your models look like this:
class User < ActiveRecord::Base
has_many :reviews
end
class Review < ActiveRecord::Base
belongs_to :user
belongs_to :reviewable, polymorphic: true
end
class Shop < ActiveRecord::Base
has_many :reviews, as: :reviewable
end
You are unab...
Same Navigation Drawer in different Activities
... tutorial, to see how you can do this.
Without fragments:
This is your BaseActivity Code:
public class BaseActivity extends Activity
{
public DrawerLayout drawerLayout;
public ListView drawerList;
public String[] layers;
private ActionBarDrawerToggle drawerToggle;
private Ma...
Cross cutting concern example
...output: Just a few weeks ago I refactored a complex, but not too big code base (around 250K lines of code) for a client. In a few hundred classes one kind of logging framework was used, in another few hundred another. Then there were several thousand lines of System.out.println(*) where there reall...