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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 ...
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 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 #...
Difference between String#equals and String#contentEquals methods
...d it, I am sharing the implementations of both the methods (as of jdk 1.7.0_45)
public boolean contentEquals(CharSequence cs) {
if (value.length != cs.length())
return false;
// Argument is a StringBuffer, StringBuilder
if (cs instanceof AbstractStringBuilder) {
char v1[...
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...
How to start working with GTest and CMake
...cluded the working CMakeLists.txt below if it is helpful to anyone.
cmake_minimum_required(VERSION 2.6)
project(basic_test)
################################
# GTest
################################
ADD_SUBDIRECTORY (gtest-1.6.0)
enable_testing()
include_directories(${gtest_SOURCE_DIR}/include ${g...
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...
How to check if a value exists in an array in Ruby
... as pointed out by @campaterson. So within Rails, or if you require 'active_support', you can write:
'Unicorn'.in?(['Cat', 'Dog', 'Bird']) # => false
OTOH, there is no in operator or #in? method in Ruby itself, even though it has been proposed before, in particular by Yusuke Endoh a top notch ...
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 ...
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...