Scilab/C4/File-handling/English-timed

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Time Narration
00:01 Welcome to this spoken tutorial on File Handling using Scilab.
00:06 In this tutorial, we will learn
00:08 file handling with the following functions:
00:11 Write Function
00:12 Read Function
00:14 mopen
00:15 mclose
00:16 For demonstration I am using Ubuntu Linux 12.04 operating system with Scilab version 5.3.3 installed.
00:26 You should have basic knowledge of Scilab.
00:29 If not, for relevant spoken tutorials please visit spoken hyphen tutorial dot org.
00:36 Now we will see some functions in Scilab which are useful for file handling.
00:41 File handling involves-
00:44 writing to a file using write() function,
00:47 reading from a file using read() function,
00:51 opening an existing file using mopen() function and
00:55 closing an already opened file using mclose() function.
01:00 Let us start with writing data to a file.
01:03 For this purpose the write() command is used.
01:07 Switch to the scilab console window.
01:10 To begin with let us create a matrix of random numbers.
01:15 Type; random underscore matrix is equal to rand into bracket 20 comma 1 close the bracket semicolon and press enter
01:29 Now check the present working directory.
01:32 Type pwd
01:34 In my case the present working directory is slash home slash fossee
01:39 Make sure that you are in a directory where you have read & write permission , before you execute these commands.
01:47 Now we will write the content of variable random underscore matrix into a text file using the write command.
01:55 Type;--> write into bracket into quotes random dash numbers dot txt close the quotes comma random underscore matrix close the bracket and press enter
02:18 Let us see whether this file has been created.
02:21 I will minimize the scilab console window.
02:23 And open the file which will be created and saved in the fossee directory of my computer.
02:33 You can see the data from variable random underscore matrix is written in a text file random dash numbers dot txt
02:42 I will close this file.
02:45 Coming back to the scilab console.
02:47 Now we will see how to read the data from a file.
02:50 For this we will use the command read as follows,
02:55 Type new underscore vector is equal to read into bracket into quote random dash numbers dot txt close the quotes comma 20 comma 1 close the bracket and press enter.
03:18 The read command reads all the data from the file mentioned in the argument,
03:23 In this case random dash numbers dot txt,
03:27 And stores in the variable new underscore vector
03:31 Press Enter to continue the display
03:35 If we modify the above command as
03:39 new underscore vector is equal to read into bracket into quote random dash numbers dot txt comma 19 comma 1
03:49 The read command reads only 19 data values from the file mentioned in this argument.
03:56 In this case random dash numbers dot txt
03:59 And stores in the variable new underscore vector.
04:03 Issue this command on the scilab console and verify the output.
04:08 Now let us see about the mopen function:
04:12 fd = mopen into bracket file-name comma mode
04:17 mopen command is used to open an existing file in a way compatible to C fopen procedure.
04:25 mode is a character string that controls whether the file is opened for
04:30 r = Opens the file for reading.
04:34 rb = Opens a binary file for reading.
04:39 rt = Opens a text file for reading.
04:43 w = Creates a new file for writing, or opens and truncates a file to zero length.
04:50 wb = Creates a new binary file for writing, or opens and truncates a file to zero length.
04:58 wt = Creates a text binary file for writing, or opens and truncates a file to zero length.
05:06 a or ab = Appends (opens a file for writing at the end of the file, or creates a file for writing).
05:14 r+ or r+b = Opens a file for update (reading and writing)
05:20 For eg fd underscore r is equal to mopen('random-numbers,'rt')
05:30 the above command opens the 'random-numbers' as a text and read-only mode.
05:37 mclose into bracket fd:
05:40 closes the opened file by using mopen.
05:43 where fd is the file descriptor of the opened file
05:48 If fd is omitted mclose closes the last opened file.
05:53 That's all we have in this tutorial.
05:55 We have learnt -
05:56 File Handling with the following functions:
05:59 write() function
06:00 Read() function
06:02 mopen
06:03 mclose.
06:05 Watch the video available at the following link.
06:08 It summarizes the Spoken Tutorial project.
06:11 If you do not have good bandwidth, you can download and watch it.
06:14 The spoken tutorial Team:
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06:23 For more details, please write to conatct@spoken-tutorial.org.
06:30 Spoken Tutorial Project is a part of the Talk to a Teacher project.
06:34 It is supported by the National Mission on Eduction through ICT, MHRD, Government of India.
06:41 More information on this mission is available at http://spoken-tutorial.org/NMEICT-Intro.
06:50 This is Anuradha Amrutkar from IIT Bombay, signing off.
06:54 Thank you for joining.

Contributors and Content Editors

PoojaMoolya, Pratik kamble, Sandhya.np14