refining algorithm

app/controllers/midways_controller.rb

@@ -88,16 +88,24 @@ def create
     #accesses the venue type and any keywords the user wants
     @midway.venue_type = params[:midway][:venue_type].downcase
     @midway.keyword = params[:midway][:keyword].downcase
+    @midway.choice = params[:midway][:choice].downcase
 
     #assigns the midpoint
     midpoint_service = MidpointService.new(addresses: participants_locations, time_option: time_option, future_datetime: future_datetime)
-    midpoint_coordinates = midpoint_service.calculate[0]
+    if @midway.choice == "efficient"
+      results = midpoint_service.calculate_efficient
+      midpoint_coordinates = results[0]
+      durations = results[1]
+    else
+      results = midpoint_service.calculate_equal
+      midpoint_coordinates = results[0]
+      durations = results[1]
+    end
     @midpoint = "#{midpoint_coordinates[:lat]},#{midpoint_coordinates[:lng]}"
     @midway.midpoint = @midpoint
     @midway.save!
 
     #assigns a duration to each Midway Participant
-    durations = midpoint_service.calculate[1]
     participants.each_with_index do |participant, index|
       participant.duration_to_midpoint = durations[index]
       participant.save!
@@ -229,7 +237,7 @@ def show
     private
 
   def midway_params
-    params.require(:midway).permit(:friends, :time_option, :future_time, :future_date, :future_datetime, :venue_type, :venue, :keyword)
+    params.require(:midway).permit(:friends, :time_option, :future_time, :future_date, :future_datetime, :venue_type, :venue, :keyword, :choice)
   end
 
   def venue_params

app/services/midpoint_service.rb

@@ -11,7 +11,7 @@ def initialize(attributes = {})
     @midpoint = { lat: 0, lng: 0 }
   end
 
-  def calculate
+  def calculate_efficient
 
     # find the average lat and long of all user locations (set this to variable D) - this is the first attempt at the midpoint (based purely off geographical equidistance)
 
@@ -33,7 +33,8 @@ def calculate
     p address_query
 
     candidates = []
-    5.times do
+    user_candidates = []
+    3.times do
 
       url = "https://api.distancematrix.ai/maps/api/distancematrix/json?units=imperial&origins=#{address_query}&destinations=#{@midpoint[:lat]},#{@midpoint[:lng]}&transit_mode=subway&mode=transit&#{url_time}&key=#{ENV["DISTANCE_MATRIX_KEY"]}"
 
@@ -48,6 +49,7 @@ def calculate
       durations = @addresses.map { |address| address[:duration] }
       max_duration = durations.max
       md_index = durations.index(max_duration)
+      min_duration = durations.min
 
       durations_text = @addresses.map { |address| address[:duration_text] }
 
@@ -57,28 +59,146 @@ def calculate
       percentage = avg / max_duration
       @midpoint[:lat] = lerp(@addresses[md_index][:lat], @midpoint[:lat], percentage)
       @midpoint[:lng] = lerp(@addresses[md_index][:lng], @midpoint[:lng], percentage)
-      min_duration = durations.min
 
       # stores as candidate_duration the discrepancy between the largest/smallest travel time
 
       candidate_duration = (max_duration - min_duration).abs
-      candidates.push([@midpoint, candidate_duration, durations_text])
+      candidates.push([@midpoint, candidate_duration, durations_text, avg])
+    end
+
+      # also puts as candidate midpoints the home locations of each of the users
+
+    @addresses.each do |address|
+      url = "https://api.distancematrix.ai/maps/api/distancematrix/json?units=imperial&origins=#{address_query}&destinations=#{address[:lat]},#{address[:lng]}&transit_mode=subway&mode=transit&#{url_time}&key=#{ENV["DISTANCE_MATRIX_KEY"]}"
+
+      @matrix = JSON.parse(open(url).read, symbolize_names: true)
+
+      @addresses.each_with_index do |address, index|
+        address[:duration] = @matrix[:rows][index+1][:elements][0][:duration][:value]
+        address[:duration_text] = @matrix[:rows][index+1][:elements][0][:duration][:text]
+      end
+
+      # determines the longest route between a user and @midpoint
+      durations = @addresses.map { |address| address[:duration] }
+      max_duration = durations.max
+      md_index = durations.index(max_duration)
+      min_duration = durations.min
+      durations_text = @addresses.map { |address| address[:duration_text] }
+      avg = (durations.sum / durations.count).to_f
+
+      candidate_duration = (max_duration - min_duration).abs
+      user_candidates.push([address, candidate_duration, durations_text, avg])
     end
 
-      # of the 5 attempts, selects the midpoint with the smallest discrepancy (candidate_duration)
+      # of all the 5 attempts, selects the midpoint with the smallest discrepancy (candidate_duration)
       # returns the chosen midpoint
 
     candidate_durations = candidates.map { |candidate| candidate[1] }
     minimum_candidate_duration = candidate_durations.min
     mcd_index = candidate_durations.index(minimum_candidate_duration)
     candidate_midpoints = candidates.map { |candidate| candidate[0] }
     @midpoint = candidate_midpoints[mcd_index]
+    p "Candidates:"
     p candidates
-    p candidate_durations
+    p "_________"
+    # p candidate_durations
+    p "User Candidates"
+    p user_candidates
+    p "_________"
     p @midpoint
 
+      # then it checks that this midpoint does not have an average duration greater than any of the user locations
+      # if it does it reassigns
+
+    candidate_averages = candidates.map { |candidate| candidate[3] }
+    midpoint_average = candidate_averages[mcd_index]
+    p midpoint_average
+    user_candidate_midpoints = user_candidates.map { |candidate| candidate[0] }
+    user_candidate_averages = user_candidates.map { |candidate| candidate[3] }
+    min_user_candidate_average = user_candidate_averages.min
+    p min_user_candidate_average
+    mucd_index = user_candidate_averages.index(min_user_candidate_average)
+    if midpoint_average > user_candidate_averages.min
+      @midpoint = user_candidate_midpoints[mucd_index]
+      user_candidate_durations_text = user_candidates.map { |candidate| candidate[2] }
+      @durations_text = user_candidate_durations_text[mucd_index]
+    else
+      candidate_durations_text = candidates.map { |candidate| candidate[2] }
+      @durations_text = candidate_durations_text[mcd_index]
+    end
+    p @midpoint
+
+    # p "Durations: #{@durations_text}"
+    return [@midpoint, @durations_text]
+  end
+
+  def calculate_equal
+
+    # find the average lat and long of all user locations (set this to variable D) - this is the first attempt at the midpoint (based purely off geographical equidistance)
+
+    lat_sum = @addresses.map { |address| address[:lat] }.sum
+    lng_sum = @addresses.map { |address| address[:lng] }.sum
+    @midpoint[:lat] = lat_sum / @addresses.count
+    @midpoint[:lng] = lng_sum / @addresses.count
+
+    # make the API calls to find the distances and duration between each user location and attempted midpoint
+
+    @condition = false
+    url_time = @time_option == 1 ? "arrival_time=#{@future_datetime}" : "departure_time=#{@future_datetime}"
+
+    address_query=""
+    @addresses.each do |address|
+      iaq = "|#{address[:lat]},#{address[:lng]}"
+      address_query = address_query + iaq
+    end
+    p address_query
+
+    candidates = []
+    user_candidates = []
+    3.times do
+
+      url = "https://api.distancematrix.ai/maps/api/distancematrix/json?units=imperial&origins=#{address_query}&destinations=#{@midpoint[:lat]},#{@midpoint[:lng]}&transit_mode=subway&mode=transit&#{url_time}&key=#{ENV["DISTANCE_MATRIX_KEY"]}"
+
+      @matrix = JSON.parse(open(url).read, symbolize_names: true)
+
+      @addresses.each_with_index do |address, index|
+        address[:duration] = @matrix[:rows][index+1][:elements][0][:duration][:value]
+        address[:duration_text] = @matrix[:rows][index+1][:elements][0][:duration][:text]
+      end
+
+      # determines the longest route between a user and @midpoint
+      durations = @addresses.map { |address| address[:duration] }
+      max_duration = durations.max
+      md_index = durations.index(max_duration)
+      min_duration = durations.min
+
+      durations_text = @addresses.map { |address| address[:duration_text] }
+
+      # reassigns the midpoint to a new location (skewed to be closer to the user who previously would have had to travel the longest)
+
+      avg = (durations.sum / durations.count).to_f
+      percentage = avg / max_duration
+      @midpoint[:lat] = lerp(@addresses[md_index][:lat], @midpoint[:lat], percentage)
+      @midpoint[:lng] = lerp(@addresses[md_index][:lng], @midpoint[:lng], percentage)
+
+      # stores as candidate_duration the discrepancy between the largest/smallest travel time
+
+      candidate_duration = (max_duration - min_duration).abs
+      candidates.push([@midpoint, candidate_duration, durations_text, avg])
+    end
+
+      # of all the 5 attempts, selects the midpoint with the smallest discrepancy (candidate_duration)
+      # returns the chosen midpoint
+
+    candidate_durations = candidates.map { |candidate| candidate[1] }
+    minimum_candidate_duration = candidate_durations.min
+    mcd_index = candidate_durations.index(minimum_candidate_duration)
+    candidate_midpoints = candidates.map { |candidate| candidate[0] }
+    @midpoint = candidate_midpoints[mcd_index]
+
     candidate_durations_text = candidates.map { |candidate| candidate[2] }
     @durations_text = candidate_durations_text[mcd_index]
+
     # p "Durations: #{@durations_text}"
     return [@midpoint, @durations_text]
   end

app/views/midways/new.html.erb

@@ -160,6 +160,11 @@
         <label class="string" for="midway_keyword">What cuisine do you fancy? (Optional)</label>
         <input class="form-control string required" placeholder="Italian, Indian, French..." type="text" name="midway[keyword]" id="midway_keyword">
       </div>
+
+      <div class="form-group string required midway_choice">
+        <label class="string" for="midway_choice">How would you like us to calculate our Midawy? (Optional)</label>
+        <input class="form-control string required" placeholder="Efficient or Equal" type="text" name="midway[choice]" id="midway_choice">
+      </div>
       <input type="submit" name="commit" value="Find our Midway" class="btn submit-button" id="submit-two" data-disable-with="Find our Midway">
   <!--     <p><input placeholder="Username..." oninput="this.className = ''"></p>
       <p><input placeholder="Password..." oninput="this.className = ''"></p> -->

db/migrate/20201208162629_add_choice_to_midway.rb

@@ -0,0 +1,5 @@
+class AddChoiceToMidway < ActiveRecord::Migration[6.0]
+  def change
+    add_column(:midways, :choice, :string)
+  end
+end

db/schema.rb

@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 2020_12_03_130053) do
+ActiveRecord::Schema.define(version: 2020_12_08_162629) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -81,6 +81,7 @@
     t.time "future_time"
     t.date "future_date"
     t.datetime "future_datetime"
+    t.string "choice"
     t.index ["user_id"], name: "index_midways_on_user_id"
     t.index ["venue_id"], name: "index_midways_on_venue_id"
   end