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

Question

I could use any improvements to improve my code. I think most of the method have the same layout but I am not getting the desired output, so any help would be great. If you want to see the exercise online, its called the Bachelor Nested Iteration. I really have no clue why I am not getting my desired output, to me my working out makes sense I guess.
for the get_first_name_of_season_winner method, no matter what arguments I pass through when I call it, I always get "Beth Smalls" as an output when it shouldn't be the case. If I pass "Season 29", the output should be "Ashley Yeats"
for the get_contestant_name method, it's the same thing. It always returns "Beth Smalls" no matter what occupation I pass through. For example if I call it like this
get_contestant_name(thebachelor, "Chiropractic Assistant" )
it should return "Becca Tilley" as an output but it doesn't.
for the count_contestant_by_hometown, it should return the number of contestants which are from the hometown thats passed in the method, however, no matter which argument I pass, I get the number 4 as an output.
for the get_occupation, it should return the name of the person corresponding to the hometown being passed in the method, but I always get "Beth Smalls" no matter which hometown I pass through it.
The final method, I have no idea how to do it. It takes in two arguments––the data hash and a string of a season. Iterate through the hash and return the average age of all of the contestants for that season.
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"
}
]
}
Now the methods. get_first_name_of_season_winner is
def get_first_name_of_season_winner(data, season)
#this method returns the first name of that seasons winner
#pass the season of the show, and then it returns only th FIRST NAME of the winner for that season
#iterate through the inital hash to access the season number
#then iterate through the array, to access the hash inside
#acess the "status" to get the output
data.each do |season, contestant_Data|
contestant_Data.each do |a|
a.each do |attribute, value|
if value == "Winner"
return a[:name]
end
end
end
end
end
get_first_name_of_season_winner(thebachelor, "season 29") #returns the full name of only "Beth Smalls"
get_contestant_name is:
def get_contestant_name(data, occupation) #this method takes in the data hash and an occupation string and returns the name of the woman who has that occupation
#iterate through the initial hash to access the seasons
#iterate through the seasons to access the arrays inside
#access the occupation element of the array
#return the person who has the occupation
data.each do |season, contestant_data|
contestant_data.each do |a|
a.each do |attribute, value|
if attribute == :occupation
return a[:name]
end
end
end
end
end
get_contestant_name(thebachelor, "Chiropractic Assistant" ) #returns the full name of only "Beth Smalls"
count_contestant_by_hometown is:
def count_contestant_by_hometown(data, hometown) #this method should return the number of contestants from the hometown passed
#include a counter variable
#iterate through the hash to access the seasons
#access the array
#access the hometown key in the hash
#keep count
counter = 0
data.each do |season, contestant_data|
contestant_data.each do |a|
a.each do |attribute, value|
if attribute == :hometown
counter += 1
end
end
end
end
return counter
end
count_contestant_by_hometown(thebachelor, "Denver, Colorado") #returns the number 4, I have no idea why
get_occupation is:
def get_occupation(data, hometown) #should return the occupation of of the first contestant who hails from the hometown
data.each do |season, contestant_data|
contestant_data.each do |a|
a.each do |attribute, value|
if attribute == :hometown
return a[:name]
end
end
end
end
end
get_occupation(thebachelor, "Denver, Colorado") #returns "Beth Smalls" when it should return "Ashley Yeats"
average_age_for_season is:
def average_age_for_season(data, season) #returns the average age of all contestants for that season

Answer 1

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
Note that you need to pass :"season 30", rather than simply "season 30". That's because your data is is using symbolised strings as keys, rather than just strings.
Replace your data's keys with strings:
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"
}
]
}
Then look for a string in the method:
def average_age_for(data, season)
contestants = data[season]
# vvvvvvv
contestants.sum { |contestant| contestant["age"].to_f } / contestants.count
# ^^^^^^^
end
And this takes shape.
You can then do:
1)
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"
2)
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"}
3)
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
4)
def get_occupation(data, hometown)
data.values.flatten.detect { |contestant| contestant["hometown"] == hometown }["occupation"]
end
get_occupation(thebachelor, "New York, New York")
#=> "Entertainer"

Answer 2

Generalised && Optimised Solution:
Following method will work to get whatever you need from your hash thebachelor,
def get_information(data, required, season, optional, hash= {})
data = season.nil? ? data.values.flatten : data[season]
selected = data.select { |x| (hash.inject(true) { |m, (k,v)| m &&= (x[k] == v) }) }
required_data = selected.map { |x| x[required] }
if optional == :average && required == :age
(required_data.map(&:to_i).sum / required_data.count.to_f).round(2)
else
(optional == :count) ? required_data.count : required_data
end
end
Data need to be provided as below,
data - hash input from which you want to retrieve data
required - output inner hash attribute you want in output.
season - If you want to retrieve data season specific, provide season, else nil to get from all season.
Optional - It can be set nil, unless you want count or average. Otherwise pass :count or :average as optional argument.
hash - filter option. If you want to filter inner data by attributes like :hometown or :status or :occupation. Just provide it. otherwise it will set empty hash.
See examples below,
# Get name of season winner for season 'season 29'
get_information(thebachelor, :name, :'season 29', nil, status: 'Winner')
# => ["Ashley Yeats"]
# Get name of all winners irrespective of season
get_information(thebachelor, :name, nil, nil, status: 'Winner')
# => ["Beth Smalls", "Ashley Yeats"]
# Get contestant name for occupation "Chiropractic Assistant"
get_information(thebachelor, :name, nil, nil, occupation: "Chiropractic Assistant")
# => ["Becca Tilley"]
# Count contestant by home town "Denver, Colorado"
get_information(thebachelor, :name, nil, :count, hometown: "Denver, Colorado")
# => 1
# Get occupation of contestant who hails from hometown "Denver, Colorado"
get_information(thebachelor, :occupation, nil, nil, hometown: "Denver, Colorado")
# => ["Dental Assitant"]
# Get Average age for season :"season 29"
get_information(thebachelor, :age, :"season 29", :average)
# => 26.5
This method provide moreover than you asked in your question.

Answer 3

First, I would reformat your data so it's easy to select/detect:
data = data.map { |key, value| value.transform_keys(&:to_sym).merge(season: key) }
so now it looks like
[{
season: "season 30",
name: "Beth Smalls",
age: "26",
hometown: "Great Falls, Virginia",
occupation: "Nanny/Freelance Journalist",
status: "Winner"
},...
]
Now it's much easier to filter and detect:
def get_first_name_of_season_winner(data, season)
p = ->(v) { v[:season] == season && v[:status] == 'Winner' }
data.detect(&p)[:name][/\w+/]
end
def get_contestant_name(data, occupation)
p = ->(v) { v[:occupation] == occupation }
data.detect(&p)[:name]
end
def count_contestant_by_hometown(data, hometown)
p = ->(v) { v[:hometown] = hometown }
data.select(&p).count
end
def get_occupation(data, hometown)
p = ->(v) { v[:hometown] = hometown }
data.detect(&p)[:occupation]
end
def average_age_for_season(data, season)
p = ->(v) { v[:season] = season }
ages = data.select(&p).map { |datum| datum[:age] }
ages.sum.fdiv(ages.count) unless ages.empty?
end
In general, all these problems are of two types:
1. Given an array of data, find all the items that satisfy a certain condition
2. Given an array of data, find the first item that satisfies a certain condition
And you always solve them with select/detect and a block/proc.