BASH/C2/Array-Operations-in-BASH/English-timed

Title of script: Array Operations In BASH

Author: Lavitha Pereira

Keywords: Video tutorial, Bash shell, Array

Time	Narration
00:01	Welcome to the spoken tutorial on Array operations in BASH.
00:05	In this tutorial, we will learn how to: Declare an Array and assign value to it.
00:12	* Initialize an Array during declaration.
00:15	* To find length of an Array and its n'th element.
00:20	* To print an Array.
00:22	To follow this tutorial, You should be familiar with Linux Operating System.
00:27	For relevant tutorials, please visit: spoken hyphen tutorial dot org.
00:33	For this tutorial, I am using:
00:37	* Ubuntu Linux 12.04 OS
00:41	* GNU Bash version 4.1.10
00:45	GNU Bash version 4 or above is recommended for practice.
00:50	Let us start with the definition of an Array and its characteristics.
00:55	* An Array is a variable with multiple values.
01:01	* The values can be of same or different types.
01:04	* There is no maximum limit for the size of an array.
01:08	* Array members need not be consecutive.
01:12	* Array index always starts with zero.
01:16	We will now see how to declare and assign a value to an Array.
01:21	The syntax to declare an Array is-
01:24	declare hyphen `a` arrayname
01:28	“declare” keyword is used to declare an Array.
01:31	It is a built-in command in Bash.
01:35	The syntax to assign a value to an Array is-
01:38	Name within square brackets index equals to within single quotes value.
01:46	Now, let see how to initialize an Array during declaration.
01:51	* Array can be declared and initialized at the same time.
01:56	* Elements Should be separated by a space .
02:00	Each element should be within parentheses.
02:03	The syntax is declare hyphen `a` arrayname equal to within round brackets within single quotes 'element1' , 'element2' and element3 .
02:19	Let us try an example.
02:21	Open the terminal by pressing Ctrl+Alt and T keys simultaneously.
02:28	Now Type: gedit space array.sh space &
02:36	We use the ampersand to free up the prompt. Press Enter.
02:41	Type the code as shown here, in your array.sh file.
02:47	This line declares an Array named Linux with elements - Debian, Redhat, Ubuntu and Fedora.
02:57	Here hyphen `a` is a flag.
03:00	It allows us to read and assign values to an Array.
03:05	Let us switch back to the slides.
03:07	The length of an Array can be obtained by this syntax:
03:12	Dollar sign opening curly bracket hash arrayname within square bracket At sign (@) and closing curly bracket.
03:22	The length of the n'th element can be obtained by this syntax:
03:28	Dollar sign opening curly bracket hash arrayname within square brackets `n` and closing curly bracket.
03:37	Here 'n' is the element number whose length is to be found.
03:42	All the elements of the Array can be printed using this syntax.
03:48	Dollar sign opening curly bracket arrayname within square brackets `At sign` and closing curly bracket.
03:57	Now come back to the text editor.
04:00	This line will display total number of elements in the Array Linux.
04:06	hyphen `e` enables interpretation of backslash escapes.
04:11	We have included this as we have backslash `n` at the end of the line.
04:18	The next line displays all the elements of the Array Linux.
04:23	This line displays the 3rd element of the Array Linux.
04:28	Please note that an Array always starts with index zero.
04:34	Lastly, this line displays the number of characters present in the 3rd element.
04:40	Now, switch to the Terminal.
04:42	Let's first make the file executable by typing chmod space plus x space array.sh. Press Enter.
04:56	Type: dot slash array .sh. Press Enter.
05:01	The output is displayed.
05:04	The number of elements or the length of the Array `Linux` is four.
05:10	The elements of the Array Linux are Debian, Redhat, Ubuntu and Fedora.
05:18	The 3rd element of Array Linux is Ubuntu.
05:22	And the number of characters in the third element is six, as expected.
05:29	This brings us to the end of this tutorial.
05:32	Let us summarize. Come back to our slides.
05:35	In this tutorial, we learnt to:
05:40	* Declare and assign values to an Array
05:43	* Initialize an Array during declaration
05:46	* To find length of an Array and its nth element and
05:51	* To print whole Array.
05:53	As an assignment-
05:55	Declare an array names of length 7 and find:
06:00	* the total number of elements
06:02	* print all the elements
06:04	* And print the 5th element.
06:06	Watch the video available at the link shown below.
06:10	It summarizes the Spoken-Tutorial project.
06:13	If you do not have good bandwidth, you can download and watch it.
06:18	The Spoken Tutorial Project team:
06:20	Conducts workshops using spoken tutorials.
06:24	Gives certificates to those who pass an online test.
06:27	For more details, please write to contact@spoken-tutorial.org.
06:35	Spoken Tutorial Project is a part of the "Talk to a Teacher" project
06:40	It is supported by the National Mission on Education through ICT, MHRD, Government of India.
06:47	More information on this mission is available at the link shown below.
06:52	The script has been contributed by FOSSEE and spoken-tutorial teams.
06:58	This is Ashwini Patil from IIT Bombay.
07:02	Thank you for joining.

Contributors and Content Editors

PoojaMoolya, Pratik kamble, Ranjana, Sandhya.np14