Ruby

In Ruby, everything is an object. More precisely, everything in Ruby is a fully functional object. So, in Ruby, the number 4, the fixed-point number 3.14, and the string "Hi" are all objects. Obviously, they are a bit "special" because you don't

Ruby has three classes of variables, one constant, and two strict pseudo variables (pseudo-variables). There are no types for variables and constants. Although there are some drawbacks to the untyped variable, there are more advantages and good

1 Using multiple construction methods There are no constructors in Ruby like C + + or Ruby, but we can still create a similar number of constructors: Ruby Code Class Coloredrectangle def initialize (R, G, B, S1, S2) @r, @g, @b, @s1, @s2 = R, G,

This article mainly introduces the example of Ruby optimization inheritance class, this article directly gives an example of optimization and implementation code, the need for friends can refer to the following In the rails principle there is the

You create an array by listing the elements in square brackets and separating them from each other by commas. The array of Ruby can accommodate different object types ruby> ary = [1, 2, "3"] [1, 2, "3"] Just like the string mentioned earlier.

Dynamic programming solves the problem of matrix multiplication, randomly produces matrix sequence, output form ((A1 (A2A3)) (A4A5) results. Code: #encoding: Utf-8 =begin author:xu jin, 4100213 date:oct, Matrixchain to find a optimum order by

The calculation of the shortest editing distance is realized by using dynamic programming algorithm. Copy Code code as follows: #encoding: Utf-8 #author: Xu Jin #date: Nov 12, 2012 #EditDistance #to find the minimum cost by using

In the Java language, a launch mechanism is provided by which the object can be constructed from a string, can get all the methods of the object (including private methods), can invoke the private method, and can change the value of the member

In Ruby we define a WC method that is used to count the number of lines of text, words, and characters that appear in a file, and the Ruby Code program is as follows: Copy Code code as follows: def WC (filename) nline = Nword = NCHAR = 0

Ruby is a language with strong expressive power, this is proud of its extraordinarily rich operator and grammatical sugars, although Ruby has always been one of its philosophies with the least surprising principle, but it is often seen as a

Recently I got a lot of pictures from the designer, the results are 1.png,2.png such file name, they also need to make these files into a readable file name, do not want one to be modified, so wrote a simple script to achieve a lot of multiple files

Active record makes it easy to implement CRUD database basics, in the following sections we use the Orders table in the MySQL database for CRUD operations, this time we look at the creation. We're supposed to have a model called Order: Class

ActiveRecord is an object-relational mapping (ORM) layer provided by rails, starting with the basics of active record, connecting databases, mapping tables, accessing data, and more. Active record uses basic ORM mode: tables are mapped to classes,

So the implementation of our shopping cart is complete, and we can use Ruby's rdoc to generate documentation for our programs, like Dotnet,java,python, RDoc can extract the annotations from the class and method declarations in our code to generate

In the previous essay, we completed the deletion of a table product, you must have noticed that we have not added any validation, such as price, we can enter any character, without error prompts. This time, let's take a look at how to add the

A one-to-one association, or, more correctly, a pair of 0 or one-to-one associations, is implemented by a foreign key reference to at most one record in another table, and the following figure describes the relationship between the Orders table and

1. Input: Yum install Ruby1.1 Error downloading Packages If installation file is wrong:Input: Yum Clean allinput:yum Makecache, at this point if error cannot find a valid BaseURL for repo:base/7/x86_64,Open Vi/etc/sysconfig/network-scripts/ifcfg-enp4

Recently, I finally took some time to study ha automated testing. Some time ago, I initially determined the design direction of automated testing and started to use Ruby as the script language and watir as the design tool, conducts automated testing

How to compile and install ruby source code in win7, and how to compile win7ruby source code At work, we need to embed ruby c api in c ++ Code. However, compilation fails in the vs project, so we can find the reason by manually compiling ruby from

[Linux] how to install and use PHP programmers in Linux Currently, the mainstream servers are Linux systems, and the mainstream releases are CentOS. The latest CentOS version number is 7.3, and my company uses CentOS. centOS of Version x. In the