Difference between revisions of "Scilab/C4/File-handling/English-timed"
From Script | Spoken-Tutorial
PoojaMoolya (Talk | contribs) |
PoojaMoolya (Talk | contribs) |
||
| Line 339: | Line 339: | ||
| 05.37 | | 05.37 | ||
| − | ||mclose into bracket fd: | + | ||'''mclose into bracket fd''': |
|- | |- | ||
Revision as of 15:04, 7 March 2014
| 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. |
