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

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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 values to it.
00:12 Initialize an array during declaration.
00:15 To find length of an array and its nth 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 ampersand (&)
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 our 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 brackets "At" sign (@) and closing curly bracket.
03:22 The length of the nth 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 our 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 third 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 learned 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