Class: Roebe::TheCollatzProblem

Inherits:
Base show all
Defined in:
lib/roebe/math/the_collatz_problem.rb

Overview

Roebe::TheCollatzProblem

Constant Summary collapse

TRY_THIS_NUMBER_BY_DEFAULT =
#

TRY_THIS_NUMBER_BY_DEFAULT

#
19

Constants inherited from Base

Base::COLOURS, Base::HOME_DIRECTORY_OF_USER_X, Base::N, Base::NAMESPACE

Instance Method Summary collapse

Methods inherited from Base

#actions, #append_this_onto_that_file, #append_what_into, #be_silent, #be_verbose?, #beautiful_url, #burlywood, #call_next, #chdir, #cheerful_guy, #cliner, #complex_esystem, #convert_global_env, #copy_directory, #copy_file, #cornflowerblue, #create_directory, #crimson, #current_month?, #current_time?, #current_year?, #cyan, #darkcyan, #darkgreen, #darkkhaki, #darkslateblue, #deeppink, #delete_symlink, #do_not_use_the_base_colours, #do_use_the_base_colours, #e, #ecomment, #editor_to_use?, #efancy, #eimp, #emphasis, #ensure_main_encoding, #ensure_utf_encoding, #eparse, #erev, #esteelblue, #etomato, #ewarn, #exit_program, #firebrick, #get_current_day, #get_current_month, #get_files_and_directories, #get_files_from, #get_german_name_for_this_weekday, #gold, #green, #grey, #hh_mm_ss, #hh_mm_ss_day_month_year, #home_dir?, #home_directory_of_user_x?, #infer_the_namespace, #internal_hash?, #is_a_directory?, #is_a_file?, #is_a_jpg_file?, #is_an_image_file?, #is_archive?, #is_audio_file?, #is_in_studium_dir?, #is_multimedia_file?, #is_on_roebe?, #is_on_windows?, #is_studium_available?, #is_symlink?, #is_this_a_ruby_file?, #is_video_file?, #iso_encoding?, #le, #left_colour, #lightblue, #lightgreen, #lightseagreen, #lightsteelblue, #lime, #limegreen, #localhost_to_data, #log_directory?, #main_encoding?, #mediumorchid, #mediumpurple, #mediumseagreen, #mediumslateblue, #mediumspringgreen, #mediumturquoise, #mkdir_p, #mv, #n_days_in_this_month, #n_pages_in_this_pdf_file?, #namespace?, #no_file_exists_at, #ogrey, #olive, #olivedrab, #open_in_browser, #opne, #opnesystem, #opnn, #orange, #orchid, #orev, #palegoldenrod, #palevioletred, #pink, #powderblue, #programs_dir?, #project_base_dir?, #random_html_colour, #rds, #read_file_in_iso_encoding, #read_file_via_the_default_encoding, #read_lines_via_iso_encoding, #readlines_with_main_encoding, #red, #register_sigint, #remove, #remove_directory, #remove_file, #rename_kde_konsole_tab, #replace_localhost_with_data, #report_pwd, #require_rescue, #reset_the_internal_hash, #return_all_directories_from_this_directory, #return_all_files_from_this_directory, #return_current_directory, #return_dd_mm_yyyy, #return_file_or_directory_of, #return_files_from_pwd, #return_last_part_of_the_current_directory, #return_utc, #rev, #right_arrow?, #right_colour, #roebe_log_directory?, #rosybrown, #royalblue, #ruby_base_directory?, #run_in_background, #run_rcfiles_then_run_ata_via_qdbus, #sandybrown, #sdir, #seagreen, #set_be_verbose, #set_xorg_buffer, #sfancy, #sfile, #show_help, #silent_redirection?, #simp, #simple_esystem, #skyblue, #slateblue, #slategray, #springgreen, #steelblue, #string_italic, #swarn, #symlink, #teal, #temp_dir?, #to_camelcase, #to_counted_hash, #tomato, #touch, #try_to_require_the_beautiful_url_gem, #try_to_require_the_html_template, #try_to_require_the_open_gem, #try_to_require_the_program_information_gem, #try_to_require_the_xorg_buffer, #use_colours?, #verbose_truth, #weekday?, #word_wrap, #write_what_into, #yellow

Methods included from Base::CommandlineArguments

#append_onto_the_commandline_arguments, #clear_commandline_arguments, #commandline_arguments?, #commandline_arguments_as_string?, #commandline_arguments_without_leading_hyphens?, #first_argument?, #first_argument_without_leading_hyphens?, #has_an_argument_been_passed?, #remove_hyphened_arguments_from_the_commandline_arguments, #return_commandline_arguments_with_leading_hyphens, #second_argument?, #set_commandline_arguments

Constructor Details

#initialize(*i) ⇒ TheCollatzProblem

#

initialize

If the input number is 19 then we will see this series:

n=19: 19, 58, 29, 88, 44, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 4, 2, 1, …
#


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# File 'lib/roebe/math/the_collatz_problem.rb', line 43

def initialize(*i)
  reset
  set_commandline_arguments(i)
  run
end

Instance Method Details

#default_print(n) ⇒ Object

#

default_print

#


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# File 'lib/roebe/math/the_collatz_problem.rb', line 63

def default_print(n)
  print n, ', '
end

#reset ⇒ Object

#

reset (reset tag)

#


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# File 'lib/roebe/math/the_collatz_problem.rb', line 52

def reset
  super()
  # ======================================================================= #
  # === @try_n_runs
  # ======================================================================= #
  @try_n_runs = 24 # Limit how often we try this. Avoids infinite loops too!
end

#run ⇒ Object

#

run (run tag)

#


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# File 'lib/roebe/math/the_collatz_problem.rb', line 70

def run
  _ = first?
  if _.nil? or _.empty?
    _ = TRY_THIS_NUMBER_BY_DEFAULT
  end
  counter = 1
  n = _.to_i
  default_print(n) # Report it initially once.
  loop {
    counter += 1
    if counter > @try_n_runs
      break
    end
    # ===================================================================== #
    # if n is even, take n/2 as the next number:
    # ===================================================================== #
    if n.even?
      n = n/2
    # ===================================================================== #
    # if n is odd, take 3n+1 as the next number instead.
    # ===================================================================== #
    elsif n.odd?
      n = (3 * n) + 1 
    else
    end
    default_print(n)
  }
  e # Trailing newline makes this prettier, in my opinion.
end