Sierpinski Triangle in Ruby

ntk () — Tue, 20 May 2008 14:48:51 GMT



# From: http://gilesbowkett.blogspot.com/2008/04/ruby-golf-ascii-sierpinski-triangle.html

# Author: Brain Mitchell



# For wide terminals:

ruby -le '64.times{|y|print" "*(63-y),(0..y).map{|x|~y&x>0?" .":" A"}}'



# For thin terminals:

ruby -le '32.times{|y|print" "*(32-y),(0..y).map{|x|~y&x>0?" .":" A"}}'

Pascal's triangle in Ruby

ntk () — Fri, 26 Oct 2007 17:02:28 GMT





# cf. http://www.ruby-forum.com/topic/97105



6.times { k=0; p $*.map!{|i|k+k=i} << 1 }



# ... or ...



ar=[]; 6.times { k=0; p ar.map!{|i|k+k=i} << 1 }





# a more general approach (for polynomials)



class Polynomial



   def triangle(nterms, row, pos=nil)



      return nil if nterms < 2 || row < 1

      nterms = nterms - 2

      num_of_rows = row



      var1 = 0 + nterms   

      var2 = 1 + nterms

      var3 = 3 + nterms 

  

      ar1 = [0, 1, 0]   # first row

      var1.times { ar1.push(0) }

      var1.times { ar1.unshift(0) }



      ar2 = []

      ar3 = []

      ar4 = [[1]]



      for num in 0..(num_of_rows - 1)  



         nextnum = ar1.size - var2



         for nextn in 1..nextnum

            sum = 0

            count = 0

            ar1.each do |n|  

               count += 1 

               if count < var3 then t = sum += n; ar2 << t else break end 

            end



            ar3 << ar2.last

            ar2.clear

            ar1.shift



         end   # second for-loop



         ar1.clear

         ar1 << ar3

         ar1.flatten!



         var2.times { ar1.push(0) }

         var2.times { ar1.unshift(0) }



         ar4 << ar3

         ar3 = []



      end  # first for-loop



      if !pos.nil?

         ret = ar4.at(row).at(pos)

         return "No such position: #{pos} in row: #{row}" if ret.nil?

         ret

      else

         ar4.map! { |r| r.join('-') }

         ar4

      end

   end 

end 





puts Polynomial.new.triangle(2, 5)

puts Polynomial.new.triangle(3, 5)

puts Polynomial.new.triangle(4, 5)

puts Polynomial.new.triangle(5, 5)

puts Polynomial.new.triangle(5, 4, 8)

puts Polynomial.new.triangle(4, 9)

puts Polynomial.new.triangle(4, 9, 10)





#------------------------





class Integer

   def fak

      f=1

      (2..self).each { |i| f *= i   }

      f

   end

end



module Enumerable

   def sum

      inject { |n, m| n + m  }

   end

end



# cf. http://blade.nagaokaut.ac.jp/~sinara/ruby/math/combinatorics/array-rep_perm.rb

class Array

  def rep_perm(n)

    if n < 0

    elsif n == 0

      yield([])

    else

      rep_perm(n - 1) do |x|

	each do |y|

	  yield(x + [y])

	end

      end

    end

  end

end





nterms = 2

exponent = 80

exponent = 8



# create the same number of variable names as there are terms 

# example: ['a', 'b'] for (a+b)**3



var_names = ('a'..'z').to_a.slice(0, nterms)

#var_names = (('a'..'z').to_a << ('A'..'Z').to_a << ('aa'..'zz').to_a).flatten!.slice(0, nterms)



ar1 = []

(0..exponent).to_a.rep_perm(nterms) { |x| p x; ar1 << x if x.sum == exponent }   # example: ... if [2,6].sum == 8

ar1.reverse!



#p ar1

#puts ar1



ar2 = []



ar1.each do |term|



   #puts "term: #{term.inspect}"  # example: term: [5, 0, 0]

   count = 0

   var1 = 1

   term.each { |i| var1 *= i.fak }

   var2 = exponent.fak / var1 

   var3 = "#{var2}   (  #{ term.join('-') << '-' } )"  # prepare term for parsing with gsub below

   ar2 << var3



end



#p ar2



result = ar2.collect do |term|

   p term

   count = -1

   term.gsub!(/(\d+)-/)  { count += 1;  "#{var_names.at(count)}" << '**' << $1 << ' ' }

   term.gsub!(/^(\d+)( +)/, '\1\2*\2')

end



puts result

pascal triangle plotter XD

jonasraoni (Jonas Raoni Soares Silva) — Sat, 02 Jul 2005 03:59:46 GMT



//+ Jonas Raoni Soares Silva

//@ http://jsfromhell.com



#include 

#include 



#define MAX 16



int main () {

	int unsigned vetor[MAX], grau, i = 0, j, top, left;



	clrscr();



	printf( "Dado o grau, printar o triangulo de pascal\n" );



	while( grau > MAX && printf( "Digite um numero entre 0 e %d para o grau: ", MAX ) && scanf( "%u", &grau ) );

	while( i++ < grau && !( j = 0 ) && printf( "\n" ) )

		while( j < i && ( j == 0 && ( top = left = vetor[j] = 1 ) ? 1 : j > 0 && j < i-1 && ( top = vetor[j] ) && ( vetor[j] = left + top ) && ( left = top ) ? 1 : ( vetor[j] = 1 ) ) && printf( "%-5d", vetor[j] ) && ++j );

	getch();

	return 0;

}

DZone Snippets: triangle code

Sierpinski Triangle in Ruby

Pascal's triangle in Ruby

pascal triangle plotter XD