Scilab/C4/File-handling/English-timed

From Script | Spoken-Tutorial
Revision as of 17:17, 10 July 2014 by Pratik kamble (Talk | contribs)

Jump to: navigation, search
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 Linux12.04 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 summarises 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
06:17 Conducts workshops using spoken tutorials


06:20 Gives certificates to those who pass an online test


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