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Array

  1. The method push inserts an element to the back of the arry; the method insert inserts an element to any place of the array.

  2. The method pop removes the last element of the array; the method delete removes any specified element from the array.

  3. The method concat combines the array with another one; the method join concatenates all elements in the array separated by the specified delimiter.

String

  1. Use the method to_i to convert a string to integer.

  2. You use both single and double quotes to denote string. The difference is that single quotes preserves escape characters while double quotes interprete escape characters.

  3. The method end_with? check whether a string ends with the specified string.

  4. The method upcase returns a copy of the string with lower case letters replaced with their upper case letters; the method downcase returns a copy of the string with upper case letters replaced with their lower case letters; the method swapcase return a copy of the string with lower case letters replaced with their upper case letters and upper case character replaced with their lower case letters.

  5. Use the method strip to remove leading and trailing white spaces.

Input and Output

  1. Both the function puts and print display the content of objects on the console. The difference is that the function puts add a new line to the end if their is no one while print not.

  2. The function gets read in input from the console. You can use the chomp method to ignore new lines, i.e., you can use gets.chomp to read a single line from the console.

File and Directory

  1. You can use the method Dir.entries to query files and subdirectories in a directory.

  2. The method File.delete removes files specified files. The number of files passed as arguments is returned.

Flow Control

  1. You cannot use else if in Ruby, instead you can use elsif.

Object and Class

  1. Use methods to query all methods of an object.

  2. You’d not define a function with the same as some directly usable function/method in Ruby.

References

Aug
Load User-written Script into Ruby
Jul
Make Plots in SAS