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How to create hash for each id in Ruby

Tags:

ruby

hash

I read the following xls file with Ruby Roo.

Now I want to make hash for each studentid like this.

132 = { "Design" => 6, "English" => 5, "Humanities" => 5, .... }
134 = { "Design" => 7, "English" => 6, "Humanities" => 6, .... }
...
...

The following is what I have done. It outputs something but I need to build up to create hashes.

require_relative './subcorrelation/version'
require 'linefit'
require 'roo'
myfile='../data/msdataparts.xls'

workbook = Roo::Excel.new(myfile)
workbook.default_sheet = workbook.sheets.first

# Create a hash of the headers so we can access columns by name (assuming row
# 1 contains the column headings).  This will also grab any data in hidden
# columns.
headers = Hash.new
workbook.row(1).each_with_index {|header,i|
headers[header] = i
}

# Iterate over the rows using the `first_row` and `last_row` methods.  Skip
# the header row in the range.
((workbook.first_row + 1)..workbook.last_row).each do |row|
  # Get the column data using the column heading.
  studentid = workbook.row(row)

  puts "{#studentid}"
end

Update

Outputs of the above cord.

[132.0, "Design", 6.0, "MYC665", "S2", 7.0]
[132.0, "English", 5.0, "MYC600", "S2", 7.0]
[132.0, "Humanities", 5.0, "MYC610", "S2", 7.0]
[132.0, "Languages", 6.0, "MYJ660", "S2", 7.0]
[132.0, "Math", 6.0, "MYC620", "S2", 7.0]
[132.0, "Music", 7.0, "MYC664", "S2", 7.0]
[132.0, "PE", 6.0, "MYC650", "S2", 7.0]
[132.0, "Science", 6.0, "MYC630", "S2", 7.0]
[132.0, "Theatre", 6.0, "MYC661", "S2", 7.0]
[134.0, "Design", 7.0, "MYC665", "S2", 7.0]
[134.0, "English", 6.0, "MYC600", "S2", 7.0]
[134.0, "Humanities", 6.0, "MYC610", "S2", 7.0]
[134.0, "Languages", 6.0, "MYS610", "S2", 7.0]
...
...

enter image description here

like image 566
shin Avatar asked Feb 25 '26 03:02

shin


1 Answers

hash_of_student_and_grades = ((workbook.first_row + 1)..workbook.last_row).each_with_object({}) do |row,hash|
  # Get the column data using the column heading.
  next if workbook.row(row).nil?
  studentid = workbook.row(row)[0]
  course = workbook.row(row)[1]
  grade = workbook.row(row)[2]
  hash[studentid.to_i] ||= {}
  hash[studentid.to_i][course] = grade.to_i
end

puts hash_of_student_and_grades

should give you your desired hash.

like image 99
bjhaid Avatar answered Mar 04 '26 05:03

bjhaid