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