Solar System Wave 2

wave2.rb

class Planet

  attr_accessor :planet_hash, :name, :moons, :escape_v, :surface_temp, :type, :distance

  def initialize(planet_hash)
    @name = planet_hash[:name]
    @moons = planet_hash[:moons]
    @escape_v = planet_hash[:escape_v]
    @surface_temp = planet_hash[:temp]
    @type = planet_hash[:type]
    @distance = planet_hash[:distance]
  end

  def tell_facts
    puts "\n#{@name} is a #{@type} planet!\n\nNumber of moons: #{@moons}\nAverage Surface Temperature: #{@surface_temp}\nDistance from the Sun: #{@distance_from_the_sun}\nEscape Velocity: #{@escape_v}\n\n\n"
  end

end

class SolarSystem
  def planets
    @planets
  end

  #Takes string or array of planet names
  def initialize(planets = [])
    @planets = [planets]
    @planets.flatten!
  end

  def add_planets(new_planets)
    @planets.push(new_planets).flatten!
    print @planets
  end

  def find_distance(planet1,planet2)
    (planet1.distance - planet2.distance).abs
  end
end


#Data for each planet
mercury = Planet.new({name:"Mercury",moons:0,escape_v:4300,temp:452, type:"rocky",distance:57909175})
venus = Planet.new({name:"Venus",moons:0,escape_v:10400,temp:726,type:"rocky",distance:108208930})
earth = Planet.new({name:"Earth",moons:1,escape_v:11200,temp:281,type:"rocky",distance:149597890})
mars = Planet.new{name:"Mars",moons:2,escape_v:5000,temp:218,type:"rocky",distance:227936640}
jupiter = Planet.new{name:"Jupiter",moons:67,escape_v:59500,temp:120,type:"gaseous",distance:778412020}
saturn = Planet.new{name:"Saturn",moons:62,escape_v:35600,temp:88,type:"gaseous",distance:886715600}
uranus = Planet.new{name:"Uranus",moons:27,escape_v:21300,temp:59,type:"gaseous",distance:2870972200}
neptune = Planet.new{name:"Neptune",moons:14,escape_v:23300,temp:48,type:"gaseous",distance:4498252900}




milkyway = SolarSystem.new([mercury,venus])
puts milkyway.find_distance(mercury,venus)

#Optional Enhancement for USER INPUT
puts "Here are the planets:\n1. #{mercury.name}\n2. #{venus.name}\n3. #{earth.name}\n4. #{mars.name}\n5. #{jupiter.name}\n6. #{saturn.name}\n7. #{uranus.name}\n8. #{neptune.name}\n"

go = true
while go
  print "Type a planet's name to learn more about it, or type exit when you're finished:  "
  choice = gets.chomp.upcase

case choice
  when "MERCURY"
    puts mercury.tell_facts
  when "VENUS"
    puts venus.tell_facts
  when "EARTH"
    puts earth.tell_facts
  when "MARS"
    puts mars.tell_facts
  when "JUPITER"
    puts jupiter.tell_facts
  when "SATURN"
    puts saturn.tell_facts
  when "URANUS"
    puts uranus.tell_facts
  when "NEPTUNE"
    puts neptune.tell_facts
  when "EXIT"
    go = false
  end
end

Cleanly written and well done, but do you need this in the initialize method:

@planets = [planets]
@planets.flatten!

could it be simpler?

For Wave 2, I accomplished the learning goals. I showed that I could use an array to store a list of objects. I figured out how to combine an array of objects and individual objects into a single, one dimensional array. I also successfully wrote three methods in the class. Overall, I was pleased with the quality of the code but I learned that I could have written the code block inside the initialize method in a single line of code. It also looks like I also left an unnecessary line of code in the add_planets method. Besides those two things, I’m not sure at this point in time how I could have improved on what I wrote, but I would like to know more about deciding how many and which kind of methods belong in a single class.