From: gerry@... (Gerry Wiener)
Date: 2001-08-16T02:32:41+09:00
Subject: [ruby-talk:19809] how to speed up hash script?

I'm in the process of writing a script that will read data from a 17MB
climatology file and then hash the information according to date-time.
The script below takes approximately 14 seconds to run. An analogous
Python script takes 3 seconds to run. Is there a simple way to speed
up the Ruby script? I'm interested in the possibility of using Ruby as
an alternative to Python.

Thanks,

Gerry Wiener

class Climo
  def initialize(in_file)
    # Read in data
    @fp = File.new(in_file, "r")
    @lines = @fp.readlines()
    @fp.close()
    @num_lines = @lines.size()
    @date_format = "YYMMDDHH"
    @len_date = @date_format.size()
    
    # Store line indices in dictionary based on date field
    @dict = Hash.new()
    for i in 1...@num_lines
      @dict[@lines[i][0...@len_date]] = i
    end
    
    first_date = @lines[1][0...@len_date]
    last_date = @lines[@num_lines-1][0...@len_date]
    puts "first_date: ", first_date
    puts "last_date: ", last_date
  end
  

end
  
def main()
    in_file = ARGV[0]
        
    climo_obj = Climo.new(in_file)
end

main()

---------------------------------------------------------------------------------
Here's a sample of the underlying data:

WZW   60.1  132.45
80010210   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -16 -99 290   6   0
-99.000 -99.000 -99.000
80010213   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -16 -99 290   7   0
-99.000 -99.000 -99.000
80010214   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -16 -99 280   4   0
-99.000 -99.000 -99.000
80010215   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -16 -99 270   7   0
-99.000 -99.000 -99.000
80010216   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -16 -99 290   5   0
-99.000 -99.000 -99.000
80010401   -9  -9 -99.00 -9 -9 -9  -99.0  -7 -14 -99 300   9   0
-99.000 -99.000 -99.000
80010402   -9  -9 -99.00 -9 -9 -9  -99.0  -7 -14 -99 290   8  18
-99.000 -99.000 -99.000
80010403   -9  -9 -99.00 -9 -9 -9  -99.0  -7 -16 -99 330   8   0
-99.000 -99.000 -99.000
80010404   -9  -9 -99.00 -9 -9 -9  -99.0  -7 -16 -99 300  12  20
-99.000 -99.000 -99.000
80010405   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -17 -99 290  10  18
-99.000 -99.000 -99.000
80010406   -9  -9 -99.00 -9 -9 -9  -99.0  -8 -17 -99 300  10   0
-99.000 -99.000 -99.000
80010407   -9  -9 -99.00 -9 -9 -9  -99.0 -10 -19 -99 300  11  16
-99.000 -99.000 -99.000