logo
down
shadow

Rails iteration over arrays and hashes


Rails iteration over arrays and hashes

Content Index :

Rails iteration over arrays and hashes
Tag : ruby-on-rails , By : WuJanJai
Date : November 25 2020, 07:06 PM

like below fixes the issue When you iterate over a hash, you get access to the keys and values.
If you look at what's printing out, you're getting the keys of each hash. Your output might make more sense if you set the parameters to what they actually are.
<% results.each do |continent| %>
  <% continent.each do |key, value| %>
    <%= key %>
  <% end %>
<% end %>

Comments
No Comments Right Now !

Boards Message :
You Must Login Or Sign Up to Add Your Comments .

Share : facebook icon twitter icon

Rails merging two arrays of hashes?


Tag : ruby-on-rails , By : user183526
Date : March 29 2020, 07:55 AM
wish help you to fix your issue I'm having a hard time grasping the logic I'd need to merge two arrays of hashes, It seems I've asked this question a while back in sort of a different way, I've also tried a few other things like the answers offered here: merging arrays of hashes , it looks like you first group by timestamp and then merge the values:
(a1+a2).group_by{|h| h[:timestamp]}.map{|k,v| v.reduce(:merge)}

How to merge arrays of hashes based on keys of hashes in Rails


Tag : ruby-on-rails , By : Amin Amini
Date : March 29 2020, 07:55 AM
I wish this help you I want to merge these two arrays based on uniqueness:
(first_array + second_array).uniq{|hash| hash.keys.first}

Improvements in code having iteration of nested hashes and arrays of input


Tag : ruby , By : lonehunter01
Date : March 29 2020, 07:55 AM
I hope this helps you . I think a big problem comes from the data you're passing in. Take for example, a working solution for your final issue.
To get the data for a single season, you can use:
def average_age_for(data, season)
  contestants = data[season]
  contestants.sum { |contestant| contestant[:age].to_f } / contestants.count
end

average_age_for(thebatchelor, :"season 30")
#=> 26.5
thebachelor = { 
  "season 30" => [
    {
      "name" =>      "Beth Smalls",
      "age" =>       "26",
      "hometown" =>  "Great Falls, Virginia",
      "occupation" => "Nanny/Freelance Journalist",
      "status" =>    "Winner"
    },
    {
      "name" =>       "Becca Tilley",
      "age" =>        "27",
      "hometown" =>   "Shreveport, Louisiana",
      "occupation" => "Chiropractic Assistant",
      "status" =>     "Eliminated Week 8"
    }
  ],
  "season 29" => [
    {
      "name" =>      "Ashley Yeats",
      "age" =>       "24",
      "hometown" =>  "Denver, Colorado",
      "occupation" => "Dental Assitant",
      "status" =>    "Winner"
    },
    {
      "name" =>       "Sam Grover",
      "age" =>        "29",
      "hometown" =>   "New York, New York",
      "occupation" => "Entertainer",
      "status" =>     "Eliminated Week 6"
    }
  ]
}
def average_age_for(data, season)
  contestants = data[season]
  #                                        vvvvvvv
  contestants.sum { |contestant| contestant["age"].to_f } / contestants.count
  #                                        ^^^^^^^
end
def get_first_name_of_season_winner(data, season)
  data[season].detect { |contestant| contestant["status"] == "Winner" }["name"].split.first
end

get_first_name_of_season_winner(thebachelor, "season 29")
#=> "Ashley"
def get_contestant_name(data, occupation)
  data.values.flatten.detect { |contestant| contestant["occupation"] == occupation }
end

get_contestant_name(thebachelor, "Chiropractic Assistant")
#=> {"name"=>"Becca Tilley", "age"=>"27", "hometown"=>"Shreveport, Louisiana", "occupation"=>"Chiropractic Assistant", "status"=>"Eliminated Week 8"}
def count_contestant_by_hometown(data, town)
  data.values.flatten.select { |contestant| contestant["hometown"] == town }.count
end

count_contestant_by_hometown(thebachelor, "New York, New York")
#=> 1
def get_occupation(data, hometown)
  data.values.flatten.detect { |contestant| contestant["hometown"] == hometown }["occupation"]
end

get_occupation(thebachelor, "New York, New York")
#=> "Entertainer"

How to access hashes whose keys are arrays in Rails?


Tag : ruby-on-rails , By : Mark W
Date : March 29 2020, 07:55 AM
it should still fix some issue I am trying to access data that has a structure like this (the status of each user on specific dates). As you can see, the hash keys are all arrays. This data has been retrieved from the DB using group_by. , This should work:
new_data = {}
data.each do |k, v|
  new_data[k.first] ||= []
  new_data[k.first] << { k.last => v}
end

How does Rails group arrays of hashes during form submission?


Tag : ruby-on-rails , By : Enrique Anaya
Date : March 29 2020, 07:55 AM
Related Posts Related QUESTIONS :
  • rubocop cannot load such file -- rubocop-rails
  • Malicious Bots waking up heroku free app and using up all dyno hours
  • How to do RSpec of validators?
  • Is there a way to wrap the response of all controller methods in a json object in application_controller.rb?
  • Need to implement #cache! if you want to use Cloudinary::CarrierWave::Storage as a cache storage
  • How to integrate custom bootstrap theme in activeadmin
  • How can I load an STI record using just the base STI class?
  • Getting the .each loop result with the lowest number from json
  • When and where to aggregate or perform calculations on data in RESTful Rails API
  • How do you write a conditional ternary operator inline in Ruby on Rails?
  • Why put require statement at the end of a ruby file?
  • In Rails, is it possible to display an alert without calling redirect_to or render?
  • Convert hash of hash in array of hash
  • Rails 5 tries to save the empty string as nil
  • websocket-driver was not found on deploy
  • Dangerous query method deprecation warning on Rails 5.2.3
  • Using ERB in Markdown with Redcarpet
  • How to create list of unique array items from thousands of records in Rails?
  • Undefined method 'suspend_paypal' for User
  • Any good methods to find Ruby on Rails memory leak?
  • Why does if __FILE__ == $0 not work on Heroku with Rails 5.2?
  • Rails: How to implement login and authentication where i have five different user models in rails?
  • What is the impact of changing rails secret_key_base on production?
  • how to keep heroku dyno worker alive if web dyno goes to sleep?
  • syntax error, unexpected end-of-input, expecting keyword_end. when running rspec of feature file
  • How does form_with know which method to call inside a model?
  • When using activestorage in Rails 6, how do I retain a file when redisplaying a form?
  • How to override table column value with column value from second table if it exist?
  • Comparison of !! operator vs present?
  • Error parsing Gemfile when pushing to Heroku
  • Rails 5: How to save uniq element in Array of Hash get from API's response
  • Devise: Unable to redirect to current user edit profile after sign_up
  • How to fix "fatal :unable to look up https (port 9418) (No such host is known)
  • How do I create a self-referential association table rails migration
  • How to send a variable from an action without using the URL in Rails?
  • How to use Ruby on Rails functions within plain (non ROR) Ruby file
  • Rails 6 and Google Maps for Rails
  • Ruby .map hash values to key value pair in array
  • Rails Frontend, Backend, and API
  • How to make value attribute in the select option tag to have url's in rails
  • Can I apply methods to a model.where condition to get all object created in specific month?
  • With Capybara, how do you get assertions on transient elements to work?
  • Best way to combine results of two select statements without returning an array?
  • How add extra attribute in model object response in rails
  • How can I block file uploads in Rails?
  • how does has_many :through work with only two models?
  • validating attribute presence with condition
  • How to fix "Illegal Argument Exception" when creating an Elasticsearch index for a Rails model?
  • Rails / Ruby how to always show decimal precision
  • Problem accessing images uploaded to heroku thru RoR application
  • How do I create a new path/route in Ruby and then link to it?
  • Rails Migration To Add Index To The Difference Between 2 Columns
  • i am trying to show my posts title on show page but it shows this error again and again . i am beginner in rails
  • Syntax Error for Ruby on Rails "(" unexpected
  • Upgrading from Rails 4.2.1
  • Reset master to an empty state
  • Ruby .round() function rounding off the values, but storing the original value only in database
  • Is it possible to email users who are @mentioned in rails ActionText?
  • Skip Current Migrations but Apply Future Ones
  • How to handle data with two has_many associations
  • shadow
    Privacy Policy - Terms - Contact Us © scrbit.com