Difference between revisions of "Scilab/C2/Iteration/English-timed"

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{| border=1
 
{| border=1
|| ''Time'''
+
|| '''Time'''
 
|| '''Narration'''
 
|| '''Narration'''
 
  
 
|-
 
|-
  
|00.01
+
|00:01
  
| | Welcome to the spoken tutorial on iterative calculations using Scilab.
+
| | Welcome to the spoken tutorial on '''iterative calculations''' using '''Scilab'''.
  
 
|-
 
|-
  
| 00.07
+
| 00:07
  
| | I am using scilab version 5.2 in Mac operating system ,
+
| | I am using '''Scilab version 5.2''' in '''Mac operating system'''
  
 
|-
 
|-
  
| 00.11
+
| 00:11
  
| | but these calculations should work in other versions and also in Scilab that runs in linux and windows.
+
| | but these calculations should work in other versions and also in Scilab that runs in '''Linux''' and '''Windows'''.
  
 
|-
 
|-
  
| 00.17
+
| 00:17
  
| | I will use the code available in the file iteration.sce
+
| | I will use the code available in the file 'iteration.sce'.
  
 
|-
 
|-
  
|00.22
+
|00:22
  
|| I have opened this file using Scilab editor, which I plan to use only as an editor.
+
|| I have opened this file using Scilab editor which I plan to use only as an editor.
  
 
|-
 
|-
  
| 00.29
+
| 00:29
  
|| Let us create a vector using the colon operator i is equal to 1 colon 5.
+
|| Let us create a vector using the colon operator. 'i' is equal to 1 colon 5,
  
 
|-
 
|-
  
| 00.38
+
| 00:38
  
 
| |creates a vector from 1 to 5, in increments of 1.
 
| |creates a vector from 1 to 5, in increments of 1.
Line 48: Line 47:
 
|-
 
|-
  
|00.42
+
|00:42
  
| | In this command,  i is equal to 1 colon 2 colon 5,
+
| | In this command,  'i' is equal to 1 colon 2 colon 5.
  
 
|-
 
|-
  
| 00.51
+
| 00:51
  
 
| | We see that the middle argument of 2 indicates the increment.
 
| | We see that the middle argument of 2 indicates the increment.
Line 60: Line 59:
 
|-
 
|-
  
| 00.56
+
| 00:56
  
| | 1 is the first argument where the vector starts. I cannot go beyond 5.
+
| | 1 is the first argument where the vector starts. 'i' cannot go beyond 5,
  
 
|-
 
|-
  
| 01.01
+
| 01:01
  
| |It can be equal to 5, however.
+
| |it can be equal to 5, however.
  
 
|-
 
|-
  
| 01.04
+
| 01:04
  
 
| | Note that if the ending argument changes to 6 the result remains the same.
 
| | Note that if the ending argument changes to 6 the result remains the same.
Line 78: Line 77:
 
|-
 
|-
  
|01.09
+
|01:09
  
| | It is not difficult to explain this behaviour.
+
| | It is not difficult to explain this behavior.
  
 
|-
 
|-
  
|01.13
+
|01:13
  
 
|  Can you think for a moment why this happens?
 
|  Can you think for a moment why this happens?
Line 90: Line 89:
 
|-
 
|-
  
| 01.15
+
| 01:15
  
|We will now demonstrate the use of the for statement to perform iterative calculations.
+
|We will now demonstrate the use of the '''for''' statement to perform iterative calculations.
  
 
|-
 
|-
  
| 01.22
+
| 01:22
  
|for i is equal to 1 colon 2 colon 7 disp i end of for loop.
+
|'''for i is equal to 1 colon 2 colon 7 disp i end''' of '''for loop'''.
  
 
|-
 
|-
  
| 01.28
+
| 01:28
  
| |I will cut this paste in scilab console press enter.
+
| |I will cut this, paste in Scilab console, press '''Enter'''.
  
 
|-
 
|-
  
| 01.34
+
| 01:34
  
| |This code prints out i, as we go through the loop.
+
| |This code prints out 'i' as we go through the loop.
  
 
|-
 
|-
  
| 01.37
+
| 01:37
  
| |The display is due to the command disp - the passed argument is displayed.
+
| |The display is due to the command '''disp''' - the passed '''argument''' is displayed.
  
 
|-
 
|-
  
| 01.42
+
| 01:42
  
| |Recall that the for loop is used for integer values.
+
| |Recall that the '''for loop''' is used for integer values.
  
 
|-
 
|-
  
| 01.45
+
| 01:45
  
 
| | In this case, four integer values, namely, 1, 3, 5 and 7 are displayed.
 
| | In this case, four integer values, namely, 1, 3, 5 and 7 are displayed.
Line 132: Line 131:
 
|-
 
|-
  
| 01.50
+
| 01:50
  
| |The number of times the iterations take place is known as priori in for loops.
+
| |The number of times the iterations take place is known as '''priori''' in '''for loops'''.
  
 
|-
 
|-
  
|01.56
+
|01:56
  
 
| | In the rest of this tutorial, we will stick to the default increment of 1.
 
| | In the rest of this tutorial, we will stick to the default increment of 1.
Line 144: Line 143:
 
|-
 
|-
  
| 02.01
+
| 02:01
  
| |Let us begin with the loop that displays i equal to 1 to 5.
+
| |Let us begin with the loop that displays 'i' equal to 1 to 5.
  
 
|-
 
|-
  
| 02.10
+
| 02:10
  
| | We will modify this code by introducing the break statement.
+
| | We will modify this code by introducing the '''break''' statement.
  
 
|-
 
|-
  
|02.18
+
|02:18
  
| Note that i is displayed only up to 2.
+
| Note that 'i' is displayed only up to 2.
  
 
|-
 
|-
  
|02.22
+
|02:22
  
 
| | The iteration is not carried out till the last value of i, namely 5.
 
| | The iteration is not carried out till the last value of i, namely 5.
Line 168: Line 167:
 
|-
 
|-
  
|02.27
+
|02:27
  
| | When i is equal to 2, the if block is executed for the first time.
+
| | When i is equal to 2, the '''if''' block is executed for the first time.
  
 
|-
 
|-
  
| 02.30
+
| 02:30
  
| | The break command, however, terminates the loop.
+
| | The '''break''' command, however, terminates the loop.
  
 
|-
 
|-
  
| 02.34
+
| 02:34
  
|| If we want to get out of a loop when some intermediate condition is satisfied, we can use the break statement.
+
|| If we want to get out of a loop when some intermediate condition is satisfied, we can use the '''break''' statement.
  
 
|-
 
|-
  
| 02.40
+
| 02:40
  
 
| | Note that "i is equal to 2" statement uses the "equal to" sign twice.
 
| | Note that "i is equal to 2" statement uses the "equal to" sign twice.
Line 192: Line 191:
 
|-
 
|-
  
| 02.45
+
| 02:45
  
 
| | This is the standard way to compare the equality in programming languages.
 
| | This is the standard way to compare the equality in programming languages.
Line 198: Line 197:
 
|-
 
|-
  
|02.50
+
|02:50
  
| | The result of this comparison statement is a boolean: true or false.
+
| | The result of this comparison statement is a '''Boolean: true or false'''.
  
 
|-
 
|-
  
| 02.56
+
| 02:56
  
| | We will introduce the continue statement here paste press enter
+
| | We will introduce the '''continue''' statement here, paste, press '''Enter'''.
  
 
|-
 
|-
  
| 03.06
+
| 03:06
  
|| This results in i getting displayed only for 4 and 5.
+
|| This results in 'i' getting displayed only for 4 and 5.
  
 
|-
 
|-
  
| 03.10
+
| 03:10
  
| | For i less than or equal to 3, as given by the i less than or equal to 3 statement, nothing happens.
+
| | For 'i' less than or equal to 3, as given by the i less than or equal to 3 statement, nothing happens.
  
 
|-
 
|-
  
| 03.18
+
| 03:18
  
| | The continue statement makes the program skip the rest of the loop.
+
| | The '''continue''' statement makes the program skip the rest of the loop.
  
 
|-
 
|-
  
| 03.22
+
| 03:22
  
| Unlike the break statement, however, it does not exit the loop.
+
| Unlike the '''break''' statement, however, it does not exit the loop.
  
 
|-
 
|-
  
| 03.25
+
| 03:25
  
| | The parameter i is incremented and all the calculations of the loop are executed for the new i.
+
| | The parameter 'i' is incremented and all the calculations of the loop are executed for the new i.
  
 
|-
 
|-
  
| 03.32
+
| 03:32
  
| | We take a small break and show how to get help for operators of the type less than or equal to.
+
| | We take a small break and show how to get help for operators of the type 'less than or equal to' (<=).
  
 
|-
 
|-
  
| 03.38
+
| 03:38
  
| |Let us type less than or equal to with help
+
| |Let us type 'less than or equal to with help'.
  
 
|-
 
|-
  
| 03.46
+
| 03:46
  
|| This opens the scilab help browser.
+
|| This opens the Scilab '''Help Browser'''.
  
 
|-
 
|-
  
| 03.51
+
| 03:51
  
|| We see that the help is available under the option less.
+
|| We see that the help is available under the option '''less'''.
  
 
|-
 
|-
  
| 03.56
+
| 03:56
  
| | So now after closing this we type help less
+
| | So now after closing this, we type '''help less'''.
  
 
|-
 
|-
  
|04.06
+
|04:06
  
|| We see the required help instructions here. I will close this.
+
|| We see the required '''help''' instructions here. I will close this.
  
 
|-
 
|-
  
|04.11
+
|04:11
  
| | The for statement in Scilab is more powerful than in programming languages.
+
| | The '''for''' statement in Scilab is more powerful than in programming languages.
  
 
|-
 
|-
  
| 04.16
+
| 04:16
  
| | For example, let us perform a loop over a vector:
+
| | For example, let us perform a '''loop''' over a '''vector''':
  
 
|-
 
|-
  
| 04.24
+
| 04:24
  
| | This script displays all values of v.
+
| | This script displays all values of 'v'.
  
 
|-
 
|-
  
| 04.28
+
| 04:28
  
 
| | Until now we have been displaying only the variables.
 
| | Until now we have been displaying only the variables.
Line 300: Line 299:
 
|-
 
|-
  
| 04.32
+
| 04:32
  
 
| | We can indeed display the result of a calculation as well.
 
| | We can indeed display the result of a calculation as well.
Line 306: Line 305:
 
|-
 
|-
  
| 04.35
+
| 04:35
  
 
| | The following code displays the square of the numbers.
 
| | The following code displays the square of the numbers.
Line 312: Line 311:
 
|-
 
|-
  
|04.44
+
|04:44
  
| | We have spent quite a bit of time explaining the for loop.
+
| | We have spent quite a bit of time explaining the '''for loop'''.
  
 
|-
 
|-
  
| 04.48
+
| 04:48
  
| | Let us now move on to the while loops.
+
| | Let us now move on to the '''while loops'''.
  
 
|-
 
|-
  
| 04.50
+
| 04:50
  
| | The while statement allows us to perform a loop when a boolean expression is true
+
| | The '''while''' statement allows us to perform a '''loop''' when a Boolean expression is '''true'''.
  
 
|-
 
|-
  
| 04.55
+
| 04:55
  
| | At the beginning of the loop, if the expression is true,
+
| | At the beginning of the '''loop''', if the expression is '''true''',
  
 
|-
 
|-
  
| 04.58
+
| 04:58
  
| |the statements in the body of the while loop are executed.
+
| |the statements in the body of the '''while loop''' are executed.
  
 
|-
 
|-
  
| 05.02
+
| 05:02
  
| | If the program is written well, the expression becomes false and the loop is ended.
+
| | If the program is written well, the expression becomes '''false''' and the '''loop''' is ended.
  
 
|-
 
|-
  
| 05.08
+
| 05:08
  
|| Now let us see an example for the while loop:
+
|| Now let us see an example for the '''while loop''':
  
 
|-
 
|-
  
|05.15
+
|05:15
  
| | The values of i, from 1 to 6 are displayed.
+
| | The values of 'i', from 1 to 6 are displayed.
  
 
|-
 
|-
  
|05.19
+
|05:19
  
|| Break and continue statements inside the while loop work exactly as they did in the for loop, as we demonstrate using break:
+
|| '''Break''' and '''continue''' statements inside the '''while loop''' work exactly as they did in the '''for loop''' as we demonstrate using '''break''':
  
 
|-
 
|-
  
|05.33
+
|05:33
  
| | We can see that the moment i becomes equal to 3, the program exits the loop, thanks to the break statement.
+
| | We can see that the moment 'i' becomes equal to 3, the program exits the '''loop''', thanks to the '''break''' statement.
  
 
|-
 
|-
  
| 05.39
+
| 05:39
  
|| You can also try the example for continue statement in while loop.
+
|| You can also try the example for '''continue''' statement in '''while loop'''.
  
 
|-
 
|-
  
| 05.44
+
| 05:44
  
| | This brings us to the end of this spoken tutorial on iterative calculations using Scilab.
+
| | This brings us to the end of this spoken tutorial on '''iterative calculations''' using Scilab.
  
 
|-
 
|-
  
| 05.50
+
| 05:50
  
 
|| Spoken Tutorials are part of the Talk to a Teacher project, supported by the National Mission on Education through ICT.
 
|| Spoken Tutorials are part of the Talk to a Teacher project, supported by the National Mission on Education through ICT.
  
 
|-
 
|-
| 05.57
+
| 05:57
 
| | More information on the same is available at the following link [http://spoken-tutorial.org/NMEICT-Intro].
 
| | More information on the same is available at the following link [http://spoken-tutorial.org/NMEICT-Intro].
  
 
|-
 
|-
| 06.00
+
| 06:00
| |Thanks for joining.Good bye.
+
| |Thanks for joining. Good bye.
  
 
|}
 
|}

Latest revision as of 20:08, 25 February 2015

Time Narration
00:01 Welcome to the spoken tutorial on iterative calculations using Scilab.
00:07 I am using Scilab version 5.2 in Mac operating system
00:11 but these calculations should work in other versions and also in Scilab that runs in Linux and Windows.
00:17 I will use the code available in the file 'iteration.sce'.
00:22 I have opened this file using Scilab editor which I plan to use only as an editor.
00:29 Let us create a vector using the colon operator. 'i' is equal to 1 colon 5,
00:38 creates a vector from 1 to 5, in increments of 1.
00:42 In this command, 'i' is equal to 1 colon 2 colon 5.
00:51 We see that the middle argument of 2 indicates the increment.
00:56 1 is the first argument where the vector starts. 'i' cannot go beyond 5,
01:01 it can be equal to 5, however.
01:04 Note that if the ending argument changes to 6 the result remains the same.
01:09 It is not difficult to explain this behavior.
01:13 Can you think for a moment why this happens?
01:15 We will now demonstrate the use of the for statement to perform iterative calculations.
01:22 for i is equal to 1 colon 2 colon 7 disp i end of for loop.
01:28 I will cut this, paste in Scilab console, press Enter.
01:34 This code prints out 'i' as we go through the loop.
01:37 The display is due to the command disp - the passed argument is displayed.
01:42 Recall that the for loop is used for integer values.
01:45 In this case, four integer values, namely, 1, 3, 5 and 7 are displayed.
01:50 The number of times the iterations take place is known as priori in for loops.
01:56 In the rest of this tutorial, we will stick to the default increment of 1.
02:01 Let us begin with the loop that displays 'i' equal to 1 to 5.
02:10 We will modify this code by introducing the break statement.
02:18 Note that 'i' is displayed only up to 2.
02:22 The iteration is not carried out till the last value of i, namely 5.
02:27 When i is equal to 2, the if block is executed for the first time.
02:30 The break command, however, terminates the loop.
02:34 If we want to get out of a loop when some intermediate condition is satisfied, we can use the break statement.
02:40 Note that "i is equal to 2" statement uses the "equal to" sign twice.
02:45 This is the standard way to compare the equality in programming languages.
02:50 The result of this comparison statement is a Boolean: true or false.
02:56 We will introduce the continue statement here, paste, press Enter.
03:06 This results in 'i' getting displayed only for 4 and 5.
03:10 For 'i' less than or equal to 3, as given by the i less than or equal to 3 statement, nothing happens.
03:18 The continue statement makes the program skip the rest of the loop.
03:22 Unlike the break statement, however, it does not exit the loop.
03:25 The parameter 'i' is incremented and all the calculations of the loop are executed for the new i.
03:32 We take a small break and show how to get help for operators of the type 'less than or equal to' (<=).
03:38 Let us type 'less than or equal to with help'.
03:46 This opens the Scilab Help Browser.
03:51 We see that the help is available under the option less.
03:56 So now after closing this, we type help less.
04:06 We see the required help instructions here. I will close this.
04:11 The for statement in Scilab is more powerful than in programming languages.
04:16 For example, let us perform a loop over a vector:
04:24 This script displays all values of 'v'.
04:28 Until now we have been displaying only the variables.
04:32 We can indeed display the result of a calculation as well.
04:35 The following code displays the square of the numbers.
04:44 We have spent quite a bit of time explaining the for loop.
04:48 Let us now move on to the while loops.
04:50 The while statement allows us to perform a loop when a Boolean expression is true.
04:55 At the beginning of the loop, if the expression is true,
04:58 the statements in the body of the while loop are executed.
05:02 If the program is written well, the expression becomes false and the loop is ended.
05:08 Now let us see an example for the while loop:
05:15 The values of 'i', from 1 to 6 are displayed.
05:19 Break and continue statements inside the while loop work exactly as they did in the for loop as we demonstrate using break:
05:33 We can see that the moment 'i' becomes equal to 3, the program exits the loop, thanks to the break statement.
05:39 You can also try the example for continue statement in while loop.
05:44 This brings us to the end of this spoken tutorial on iterative calculations using Scilab.
05:50 Spoken Tutorials are part of the Talk to a Teacher project, supported by the National Mission on Education through ICT.
05:57 More information on the same is available at the following link [1].
06:00 Thanks for joining. Good bye.

Contributors and Content Editors

Gaurav, PoojaMoolya, Sandhya.np14, Sneha