Scilab/C4/User-Defined-Input-and-Output/English-timed

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Time Narration
00:01 Welcome to the spoken tutorial onFile handling using Scilab.
00:06 In this tutorial, we will learn
00:08 Input Function
00:10 Formatting the Output
00:12 save function
00:14 load function
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 on Scilab please visit spoken hyphen tutorial dot org
00:37 The input() function is used to take the input from the user.
00:42 It provides a prompt in the text string for user input.
00:47 It waits for input from the keyboard.
00:51 If nothing but a carriage return is entered at the prompt, input() function returns an empty matrix.
00:59 The input function can be written in two ways .
01:03 First ,x= input into brackets message to display
01:09 Second,x= input into brackets ("message to display","strings").
01:17 In the second example, the second argument is “string”.
01:22 So the output is a character string, which is the expression entered using the keyboard.
01:29 Switch to the Scilab Console window and type,
01:33 x is equal to input open bracket inside double quotes Enter your age close the double quotes close the bracket and press enter.
01:49 Type 25 and press enter
01:53 Now type -->y is equal to input into bracket into double quotes Enter your age close the double quotes comma again inside double quotes write string close the bracket and press enter
02:14 type 25 and press enter
02:18 We see that in both the cases the input we entered through keyboard, was a number 25.
02:25 Now, let us check the type of variable that x and y are.
02:30 Let us clear the console using clc command.
02:34 We are doing this to validate the use and importance of the argument “string”, given in the second example.
02:42 To check the type of variable, let us type
02:45 -->typeof into brackets xand press enter
02:51 similarly; typeof(y) and press enter
02:57 You can see it yourself, that the first answer stored in x is of type constant and
03:04 second answer stored in y, with the argument “string” included in the command, is of type string.
03:12 Let us now see how to format the output that is displayed on the console.
03:17 This can be done using the mprintf() function.
03:22 mprintf() function converts, formats and writes data on to the Scilab console.
03:28 It is an interface for C-coded version of printf function.
03:34 Let us see an example for this.Switch to the console
03:38 Type-->mprintf into bracket into quotes type iteration percent i comma result is colon slash n alpha equal to percentf comma 33 comma 0.535 close the bracket,
04:12 Here 33 will be displayed in place of percent i and point 535 will be displayed in place of percent f as a flow, press enter
04:26 This will give the output as At iteration 33, Result is alpha is equal to 0.535000.
04:39 Clear the console. Now let us see another example.
04:44 In print f open bracket into quotes value of x is equal to percentage d is taken as a constant comma while value of y is equal to percent s is taken as a string close the quotes comma x comma y close the bracket
05:19 In the above example percentage d is used to insert a constant data stored in variable x and
05:28 percentage s is used to insert a string data stored in variable y. press enter you see the output
05:38 Now, let us discuss the use of save and load command.
05:43 To quit Scilab midway through a calculation and to
05:47 continue to a later stage type save thissession
05:52 This will save the current values of all variables to a file called thissession.
05:58 This file cannot be edited.
06:01 It is in binary format.
06:04 When you next start Scilab, type load thissession
06:08 and the computation can be resumed where you left off.
06:13 The purpose of save and load function are
06:16 The save() command saves all the scilab current variables in a binary file.
06:22 If the variable is a graphic handle, the save function saves all the corresponding graphics_entities definition.
06:31 The file can be given either by its paths or by its descriptor previously given.
06:37 save(filename) saves all the current variables in a file defined by filename.
06:45 save into bracket fd saves all the current variables in the file defined by the descriptor fd.
06:53 save(filename,x,y) or save(fd,x,y) saves only named variables x and y.
07:02 Let us see an example to illustrate the save and load commands usage.
07:07 Switch back to the console . Let us define two matrices say a and b
07:14 -->a = eye of (2,2) and press enter
07:22 Type;b=ones(a) and press enter
07:28 Clear the console using clc command. Now type
07:34
07:42 or it can also be written as
07:46 save into brackets into quotes matrix dash a dash b dot dat close the quotes comma a comma b close the braket and press enter
08:03 This saves the values of variables in a binary file matrix dash a dash b dot dat in the present working directory.
08:12 You can browse the present working directory to check the existence of this binary file.
08:17 You can see it here. I will close the file browser.
08:22 Now let us load the file back in to the variables.
08:26 Before this, let us clear the variables a and b
08:29 Type clear a space b press enter
08:34 Let us cross check if these variables are really cleared.
08:39 ->a
08:40 b
08:41 Now let us load back the values from the binary files in these variables a and b using the load command.
08:49 Type Load into bracket into quote matrix dash a dash b dot dat close the quotes comma into quotes a comma into quotes b close the bracket and press enter
09:08 Let us check the values in variables a and b. Clear the console.
09:14 Type >a And-->b
09:18 You can see the values are loaded back in the variables.
09:23 In this tutorial we learnt -
09:24 Input Function using input command
09:28 Formatting the Output using mprintf command
09:31 Save Function
09:33 Load Function
09:35 Watch the video available at the link shown below
09:38 It summarises the Spoken Tutorial project
09:41 If you do not have good bandwidth, you can download and watch it
09:46 The spoken tutorial Team
09:48 Conducts workshops using spoken tutorials
09:51 Gives certificates to those who pass an online test
09:54 For more details, please write to conatct@spoken-tutorial.org
10:01 Spoken Tutorial Project is a part of the Talk to a Teacher project
10:05 It is supported by the National Mission on Eduction through ICT, MHRD, Government of India.
10:12 More information on this mission is available at http://spoken-tutorial.org/NMEICT-Intro
10:23 This is Anuradha Amrutkar from IIT Bombay signing off.
10:26 Thank you for joining.

Contributors and Content Editors

Gaurav, PoojaMoolya, Pratik kamble, Sandhya.np14