From yesterday's Ruby course - a whole set of new examples on Ruby collections - arrays (which are ordered lists) and hashes (which are unordered). In other words, you look somethng up in an array by its position number, whereas you look something up in a hash based on its unique key, and the way it's implemented, you cannot sort those keys - if you try, you get an array or arrays of two elements returned!

[example] - Sorting an array and iterating through it in various ways

[example] - Using an anonymous array to swap over two variables easily

[exampe] - Combining arrays with "and" and "or"

[example] - sorting a hash - (you can't, but this shows how to get the same effective result!)

[example] - multidimensional structures in Ruby - a hash or arrays in this case


Here are some other examples from yesterday too - string handling and exceptions:

[example] - lots of ways of defining and handling strings

[example] - cleaning up strings of text that are user input using string methods and regular expressions

[example] Using a constant to turn debug mode on and off - also a very good example of reading from and processing a file in Ruby

(written 2010-02-03 07:28:50)

 R107 - Collections (Arrays and Hashes) in Ruby
  [2618] What are Ruby Symbols? - (2010-02-02)
  [2606] Sorting arrays and hashes in Ruby - (2010-01-30)
  [2291] Collection objects (array and hash) in Ruby - (2009-07-16)
  [991] Adding a member to a Hash in Ruby - (2006-12-16)

R109 - Ruby - Strings and Regular Expressions
  [2623] Object Oriented Ruby - new examples - (2010-02-03)
  [2614] Neatly formatting results into a table - (2010-02-01)
  [2608] Search and replace in Ruby - Ruby Regular Expressions - (2010-01-31)
  [2295] The dog is not in trouble - (2009-07-17)
  [2293] Regular Expressions in Ruby - (2009-07-16)
  [1891] Ruby to access web services - (2008-11-16)
  [1887] Ruby Programming Course - Saturday and Sunday - (2008-11-16)
  [1875] What are exceptions - Python based answer - (2008-11-08)
  [1588] String interpretation in Ruby - (2008-03-21)
  [1305] Regular expressions made easy - building from components - (2007-08-16)
  [1195] Regular Express Primer - (2007-05-20)
  [987] Ruby v Perl - interpollating variables - (2006-12-15)
  [986] puts - opposite of chomp in Ruby - (2006-12-15)
  [970] String duplication - x in Perl, * in Python and Ruby - (2006-12-07)

R111 - Ruby - Exceptions.
  [2622] Handling unusual and error conditions - exceptions - (2010-02-03)
  [2620] Direct access to object variable (attributes) in Ruby - (2010-02-02)
  [2615] String to number conversion with error trapping in Ruby - (2010-02-01)

R118 - Ruby Sources and Resources
  [2610] Cheat Sheet - what do you need for Ruby on Rails? - (2010-01-31)
  [550] 2006 - Making business a pleasure - (2006-01-01)

R106 - Input and Output in Ruby
  [2290] Opening and reading files - the ruby fundamentals - (2009-07-16)
  [1587] Some Ruby programming examples from our course - (2008-03-21)

Back to Direct access to object variable (attributes) in Ruby

Previous and next or Horse's mouth home

Forward to Handling unusual and error conditions - exceptions

Both feet on the same pavement
Skyline and looking up in London
Ruby collections and strings - some new examples
Passing code to procedures and yield in Ruby
Comparing floating point numbers - a word of caution and a solution
Defining a static method - Java, Python and Ruby