class DataCalc

Attributes

input[RW]

length[RW]

output[RW]

Public Class Methods

new(input) click to toggle source

# File lib/datacalc.rb, line 6
def initialize(input)
  @input = JSON.parse(input)
  @length = @input.length
  @output = nil
end

Public Instance Methods

match(*matchnames) click to toggle source

What: Gets list entries that include all values of arguments passed Input: Variable number of arrays with field name and value Output: Parsed JSON of entries that match all input arrays

# File lib/datacalc.rb, line 26
def match(*matchnames)
  savefile = "[]"
  matchnames.each do |match|
    tmpfile = Array.new
    (0..@length-1).each do |l|
      if match[1] == (@input[l])[match[0]]
        tmpfile << @input[l]
        savefile = tmpfile.to_json
      end
    end
    @input = JSON.parse(savefile)
    @length = @input.length
  end
  @output = @input
end

mean(col) click to toggle source

What: Get average of a column Input: Column to get average of Output: Average

# File lib/datacalc.rb, line 59
def mean(col)
  mean = sum(col).to_f / @length.to_f
end

sortalpha(sattr) click to toggle source

What: Sorts in alphabetical order Input: Attribute to sort by Output: Sorted JSON

# File lib/datacalc.rb, line 52
def sortalpha(sattr)
  @input.sort_by {|e| e[sattr]}.to_json
end

sortnum(sattr) click to toggle source

What: Sorts in numerical order Input: Attribute to sort by Output: Sorted JSON

# File lib/datacalc.rb, line 45
def sortnum(sattr)
  @input.sort_by {|e| e[sattr].to_i}.to_json
end

sum(col) click to toggle source

What: Gets the sum of a column Input: Column to add up Output: Sum for column

# File lib/datacalc.rb, line 15
def sum(col)
  total = 0
  (0..@length-1).each do |l|
    total += (@input[l])[col].to_i
  end
  return total
end