I need some help at my recursion function to get it run.
I had a database table with following attributes:
id
title
parent_id
Some example entries would be:
1,title1, 0
2,title2, 1
3,title3, 1
4,tilte4, 0
5,title5, 3
with these entries I wants to create the following nested list
title1
title2
tille3
title5
title4
I write the following functions to generate these but there is a failure in there which overfolows my stack always
def topic_nested_list(topics_list)
get_nested_list(topics_list, topics_list.first)
end
def get_nested_list(topics, parent)
ul_contents = ""
ul_contents << "<ul>"
childs = get_topic_childs(topics,parent.id)
if childs.blank?
ul_contents << "<li>" << parent.title << "</li>"
else
for child in topics
ul_contents << get_nested_list(topics, child)
end
end
ul_contents << "</ul>"
end
def get_topic_childs(topic_list, id)
childs = []
topic_list.each do |topic|
if topic.parent_id == id
childs.push(topic)
end
end
return childs
end
I am not too sure everything that your code is doing, but it seems you want something like this
def process_topics topics_list
topics_list.each do |t|
# do something
process_topics children_of_topic(topic_list, t)
# or do something
end
end
def children_of_topic(topic_list, topic)
topic_list.select(|t| t.id == topic.parent_id)
end
It might be good to simplify your example down to something like this then add stuff in as you go.
Your very first call
get_nested_list(topics_list, topics_list.first)
Is not making sense. You want to cycle through each topic in your list and get the children of that topic and then recurse on that.
Related
First of all I beg your pardon if this question already exists, I deeply searched for a solution here but I've been able to find it, nevertheless I feel it's a problem so common that is seems so strange to not find anything here...
My struggle is the following: given an hash, I need to return all the PATHS to each leaf as an array of strings; so, for example:
{:a=> 1} gives ['a']
{:a=>{:b=>3, :c=>4} returns an array with two results: ["a.b", "a.c"]
{:a=>[1, {:b=>2}]} will result in ["a.0", "a.1.b"]
and so on...
I have found only partial solutions to this and with dozens of codelines. like this
def pathify
self.keys.inject([]) do |acc, element|
return acc if element.blank?
if !(element.is_a?(Hash) || element.is_a?(Array))
if acc.last.is_a?(Array)
acc[acc.size-1] = acc.last.join('.')
else
acc << element.to_s
end
end
if element.is_a?(Hash)
element.keys.each do |key|
if acc.last.is_a?(Array)
acc.last << key.to_s
else
acc << [key.to_s]
end
element[key].pathify
end
end
if element.is_a?(Array)
acc << element.map(&:pathify)
end
acc
end
end
But it does not work in all cases and is extremely inefficient. Summarizing: is there any way to "pathify" an hash to return all the paths to each leaf in form of array of strings?
Thank you for the help!
Edited
Adding some specs
for {} it returns []
for {:a=>1} it returns ["a"]
for {:a=>1, :b=>1} it returns ["a", "b"]
for {:a=>{:b=>1}} it returns ["a.b"] (FAILED - 1) got: ["a"]
for {:a=>{:b=>1, :c=>2}} it returns ["a.b", "a.c"] (FAILED - 2) got: ["a"]
for {:a=>[1]} it returns ["a.0"] (FAILED - 3) got: ["a"]
for {:a=>[1, "b"]} it returns ["a.0", "a.1"] (FAILED - 4) got: ["a"]
def show(key, path)
if path.is_a? Array
path.map {|p| "#{key}.#{p}"}
else
path == "" ? key.to_s : "#{key}.#{path}"
end
end
def pathify(input)
if input.is_a? Hash
input.map do |k,v|
sub_path = pathify(v)
show(k, sub_path)
end.flatten
elsif input.is_a? Array
input.map.with_index do |v, i|
sub_path = pathify(v)
show(i, sub_path)
end.flatten
else
""
end
end
def leaf_paths(enum)
return unless [Hash, Array].include? enum.class
[].tap do |result|
if enum.is_a?(Hash)
enum.each { |k, v| result = attach_leaf_paths(k, v, result) }
elsif enum.is_a?(Array)
enum.each_with_index { |elem, index| result = attach_leaf_paths(index, elem, result) }
end
end
end
def attach_leaf_paths(key, value, result)
if (children = leaf_paths(value))
children.each { |child| result << "#{key}.#{child}" }
else
result << key.to_s
end
result
end
This is very similar to https://github.com/wteuber/yaml_normalizer/blob/b85dca7357df00757c471acb5dadb79a53dd27c1/lib/yaml_normalizer/ext/namespaced.rb
So I tweaked the code a bit to fit your needs:
module Leafs
def leafs(namespace = [], tree = {})
each do |key, value|
child_ns = namespace.dup << key
if value.instance_of?(Hash)
value.extend(Leafs).leafs child_ns, tree
elsif value.instance_of?(Array)
value.each.with_index.inject({}) {|h, (v,k)| h[k]=v; h}.extend(Leafs).leafs child_ns, tree
else
tree[child_ns.join('.')] = value
end
end
tree.keys.to_a
end
end
Here is how to use it:
h = {a: [1, "b"], c: {d:1}}
h.extend(Leafs)
h.leafs
# => ["a.0", "a.1", "c.d"]
I hope you find this helpful.
def pathify(what)
paths = []
if what.is_a?(Array)
what.each_with_index do | element, index |
paths+= pathify(element).map{|e| index.to_s + '.' + e.to_s}
end
elsif what.is_a?(Hash)
what.each do |k,v|
paths+= pathify(v).map{|e| k.to_s + '.' + e.to_s}
end
else
paths.append('')
end
paths.map{|e| e.delete_suffix('.')}
end
I was handed a project from someone else, it's in Ruby On Rails, which I know VERY LITTLE. Basically, there is an EXPORT button, that the user clicks to send data to a CSV. I am tasked with sending this data to the view to be seen in HTML. (Thinking I could use dataTables). I have tried following examples, such as:
#example = StudentGroup.where(survey_id: #survey.id).order("groupNum")
and then using <%= #example %> in the view just to see the data and I get nothing. (Also extremely new to MySQL). I'll post the method, if ANYONE can help me, I'd very much appreciate it.
def download_results
if (user_signed_in?)
else
redirect_to new_user_session_path
end
#survey = Survey.find(params[:survey_to_view])
filename = #survey.name + " - " + Date.today.to_formatted_s(:short)
require "csv"
CSV.open(#survey.name+".csv", "wb") do |csv|
csv << [filename]
StudentGroup.where(survey_id: #survey.id).order("groupNum")
csv << []
csv << ["Summarized Results"]
csv << ["UCA","Group Number","Criteria 1","Criteria 2","Criteria 3","Criteria 4","Criteria 5","Criteria 6","Criteria 7","Criteria 8","Overall Team Contribution","Average(Would Work With Again)","Average(C1..C8)","Overall Team Contribution MINUS Average(C1..C9)"]
questions = #survey.questions
numQuestions = 0
questions.each do |q|
if(q.question_type != 2 && q.question_type != 4)
numQuestions = numQuestions+1
end
end
groups.each do |g|
answersCount = Answer.where(student_group_id: g.id).count
if(answersCount == numQuestions && answersCount != 0)
othersInGroup = StudentGroup.where(groupNum: g.groupNum, survey_id: #survey.id).order("groupNum")
size = othersInGroup.count-1
arr = []
criteria = SurveyQuestionDatum.where("number > 24 AND number < 35")
multiAvg = 0
teamCont = 0
criteria.each do |c|
avg = 0
othersInGroup.each do |o|
a = Answer.where(survey_question_datum_id: c.id, student_group_id: o.id).first
if(o.uca != g.uca)
if(a.nil?)
size = size-1
else
avg = avg + a.answer[g.uca].to_i
end
end
end
avg = avg.to_f/size
if(c.number == 33)
teamCont = avg
end
if(c.number < 33)
multiAvg = multiAvg+avg
end
arr << avg
end
multiAvg = multiAvg.to_f/8
arr << multiAvg
arr << teamCont-multiAvg
arr.insert(0,g.uca, g.groupNum)
csv << arr
end
end
csv << []
csv << []
csv << ["Raw Student Answers"]
groups = StudentGroup.where(survey_id: #survey.id).order("groupNum")
size = groups.count
csv << ["UCA", "F-Number", "Group Number"]
groups.each do |g|
answersCount = Answer.where(student_group_id: g.id).count
if(answersCount == numQuestions && answersCount != 0)
othersInGroup = StudentGroup.where(groupNum: g.groupNum, survey_id: #survey.id).order("groupNum")
csv << []
csv << [g.uca, g.FNum, g.groupNum]
answers = Answer.where(student_group_id: g.id)
csv << ["Question Number", "Question", "Answer"]
answers.each do |a|
datum = a.survey_question_datum
question = datum.question
#question_types = {"0" => "short", "1" => "paragraph",
#2" => "title", "3" => "fivept", "4" => "fixed",
#5" =>"ranking", "6"=>"tenpoints","7"=>"hundredpoints"}
ansText = ""
if(question.question_type == 0)
ansText = a.answer
elsif (question.question_type == 1)
if(question.rule == 'perMember')
othersInGroup.each do |o|
ansText = ansText+"#{o.uca},#{a.answer[o.uca]},"
end
elsif(question.rule == 'default')
ansText = a.answer
end
else (question.question_type == 3)
othersInGroup.each do |o|
ansText = ansText+"#{o.uca},#{a.answer[o.uca]},"
end
end
ansText = ansText.chomp(',')
ansText = ansText.split(',')
ansText.insert(0,datum.number,question.question_text)
csv << ansText
end
end
end
end
send_file(#survey.name+".csv", :filename => filename+".csv")
end
You need a new controller action. Take a look at http://guides.rubyonrails.org/layouts_and_rendering.html
Create an index (or show, or whatever you want to call it, maybe example) action. Make sure it is in your routes.
http://guides.rubyonrails.org/getting_started.html#adding-a-route-for-comments
do not use the download_results code.
set your #example variable the way you were trying to do.
create a view for your index action
add the data to your index view.
If you put code in your download_results method (action) it will never get rendered because of the send_file method call.
Did you create a brand new controller / action / view? Did you use generators? Have you really practiced doing this setup exactly the way the examples, videos, tutorials say to do it? If you have, you have seen how all the pieces (models, controllers, actions, views) come together. You should have seen how render statements come into play. Do that, exactly as the tutorials say to do it and you will get the idea.
If you want to use the same content that the download action uses, refactor the code to extract a method that is used both actions.
This is related to respond_to part, check the docs.
send_file(#survey.name+".csv", :filename => filename+".csv")
Your code above simply means you click the button, the controller will respond you with a csv file. So, if you want a html, the controller should be able to respond to html as well.
I have this function:
medIntCategory = MedicalInterventionCategory.find_by_category_text(category.category.text)
However now I have a list of categories called categories.
I would like to execute the above code for each category and get back a list of medIntCategories, but with no duplicates.
Is there a simple way to do this since I am only dealing with integers?
in simple terms:
categoryList = []
for each category in categories do
categoryList += MedicalInterventionCategory.find_by_category_text(category.category.text)
end
But with duplicate checking
This sounds like a job for Array#map and Array#uniq:
category_list = categories.map{|category|
MedicalInterventionCategory.find_by_category_text(category.category.text)
}.uniq
#result=Array.new
##assuming that it returns an array
medIntCategory = MedicalInterventionCategory.find_by_category_text(category.category.text)
##get the first category obtained
#result << medIntCategory
if medIntCategory.present?
medIntCategory.each do |m|
##add in same array only if not present
if !#result.include?(m)
#result << m.find_by_category_text(c.category.text)
end
end
##return a unique value array
#result.flatten.compact.uniq unless #result.blank?
end
HOPE IT HELPS
I think this would work
category_list = []
categories.each do |category|
category_list << MedicalInterventionCategory.find_by_category_text(category.category.text).distinct
end
To avoid making the last question full of edits, I am spinning off a new question on debugging this. Original question was this Neo4j gem - Plucking multiple nodes/relationships
This is sorta where I ended up. There is some flaw with the day detection but as a query it does work for now. #collection returns a slew of things as written.
Event.rb
def self.reminder
one_day = 1.day.to_i
time = Time.zone.now.to_i
#collection = Event.as(:e).where( "( ( e.date_start - {current_time} ) / {one_day_p} ) < {one_p} " ).users(:u, :rel).where(setting_reminder: true).rel_where(reminded: false ).params(one_day_p: one_day, current_time: time, one_p: 1).pluck(:e, 'COLLECT(u)', 'COLLECT(rel)')
#collection.each do |event, users, rels|
users.each_with_index do |user, i|
UserMailer.reminder(event,user[i]).deliver
end
rels.each_with_index do |rels, i|
rels[i].reminded = true
end
end
end
I originally had it as the last answer did, but I think I need to track both the indexes of the user and the rel nested within the each block.
Running in rails c, when I run Event.reminder I get
TypeError: 0 is not a symbol
What's wrong with my nested loop?
#collection is one big array that contains other arrays. You can't do #collection.each do |event, users, rels|, you need to return each array within it and then loop through those. Two ways:
#collection = Event.as(:e).where( "( ( e.date_start - {current_time} ) / {one_day_p} ) < {one_p} " ).users(:u, :rel).where(setting_reminder: true).rel_where(reminded: false ).params(one_day_p: one_day, current_time: time, one_p: 1).pluck(:e, 'COLLECT(u)', 'COLLECT(rel)')
#collection.each do |row|
event = row[0]
users = row[1]
rels = row[2]
users.each_with_index do |user, i|
UserMailer.reminder(event, user).deliver
rels[i].reminded = true
rels[i].save
end
end
# OR
events = collection.map { |row| row[0] }
users = collection.map { |row| row[1] }
rels = collection.map { |row| row[2] }
events.each_with_index do |event, i|
UserMailer.reminder(event, users[i]).deliver
rels[i].reminded = true
rels[i].save
end
I think you just need to do a normal each:
users.each do |user|
UserMailer.reminder(event,user).deliver
end
I have a controller like this:
def download_link
#It starts a background process to handle all these things
temp_file = Tempfile.new 'temp_file'
temp_sqlite_db = SQLite3::Database.new temp_file.path
temp_sqlite_db.execute("CREATE TABLE inspection (id INTEGER NOT NULL,desc VARCHAR(255));")
inspections = Inspection.a_heavy_query_that_doesnt_worths_to_wait_so_much_for_a_reply
# Some code inserting records and creating tables, with execute() too
# more code, compressing the db and sending an email with a download link to the zip file
end
Now, I would like to know if there's a way to replace the execute() function and maybe create the tables and save records like inspection.create(something) . Thanks in advance
If anyone needs something similar, this was my implementation:
# config/initializers/sql_returner.rb
module ActiveRecord
class Base
def sql_insert
if attributes_with_quotes.empty?
connection.empty_insert_statement(self.class.table_name)
else
"INSERT INTO #{self.class.quoted_table_name} " +
"(#{quoted_column_names.join(', ')}) " +
"VALUES(#{attributes_with_quotes.values.join(', ')});"
end
end
def self.sql_create
"CREATE TABLE #{table_name} (" +
" #{ self.columns.collect{ |column|
column_sql = " #{ column.name } #{ sql_type column } "
column_sql << " PRIMARY KEY " if column.primary
column_sql << " NOT NULL " unless column.null
column_sql
}.join(', ') } );"
end
private
def self.sql_type column
case column.type
when 'datetime', 'string'
'TEXT'
else
column.type.to_s
end
end
end
end
Then, if I need to create tables and insert records, taking the same code of the question as example, I must to run:
def download_link
temp_file = Tempfile.new 'temp_file'
temp_sqlite_db = SQLite3::Database.new temp_file.path
temp_sqlite_db.execute(Inspection.sql_create)
inspections = Inspection.a_heavy_query_that_doesnt_worths_to_wait_so_much_for_a_reply
insert = ""
inspections.each{ |insp|
insert << insp.return_insert_sql
}
#.....
end
For the first method sql_insert I took as example the create method code of ActiveRecord. I know that maybe some kittens died coding this implementation, but at least for me it works.