将Ruby 1.9.2与RubyMine和Matrix一起使用 [英] Using Ruby 1.9.2 with RubyMine and Matrix

问题描述

我正在使用ruby 1.9.2-p290和RubyMine.而且我尝试使用矩阵(需要矩阵").所以，我有几个问题.

I am using ruby 1.9.2-p290 and RubyMine. And i try to use Matrix (require 'matrix'). So, i have few questions.

• 如何更改矩阵的任何值?

例如:

require 'matrix'
matrix =  Matrix[[1, -2, 3], [3, 4, -5], [2, 4, 1]]
matrix[0, 0] = 5
p matrix

下一个:

in `<top (required)>': private method `[]=' called for Matrix[[1, -2, 3], [3, 4, -5], [2, 4, 1]]:Matrix (NoMethodError)
from -e:1:in `load'
from -e:1:in `<main>'

• 是否可以通过RubyMine IDE中的代码完成向我展示矩阵方法?
• 我应该将哪些库用于矩阵?矩阵?玛特恩?还有别的吗

推荐答案

Ad 1)我知道文档说[]=是一个公共实例方法，1.9.2中的现实似乎与之不匹配:

Ad 1) I know the documentation says that []= is a public instance method, reality in 1.9.2 does not seem to match that:

matrix.private_methods.grep(/\[\]/) #=> [:[]=]

我看到了两种解决方法.第一种是使用send绕过private:

I see two ways around this. The first is using send to bypass private:

matrix.send(:[]=, 0, 0, 5) #=> 5

第二个是通过数组:

m = *matrix
m[0][0] = 5
matrix = Matrix[*m]

如果您确实愿意，可以更改该方法的可见性:

If you really wanted to, you could change the visibility of the method:

matrix.class.class_eval { public :[]= }

请注意，我不鼓励使用这些方法，该类的实现方式强烈暗示了作者将矩阵视为不可变的对象.

Note that I don't encourage any of these, the way the class is implemented is a strong hint that the authors consider matrices to be immutable objects.

广告2)不幸的是，我并不了解RubyMine，但是可以找到Matrix类的文档

Ad 2) I don't know RubyMine unfortunately, but the documentation for the Matrix class can be found here.

广告3)我还没有在Ruby中广泛使用矩阵，但是对于我需要的它们，Matrix类已经足够了.

Ad 3) I haven't had an extensive use for matrices in Ruby yet, but for what I needed them the Matrix class was good enough.

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