Difference between revisions of "KTurtle/C3/Control-Execution/English-timed"

||Hello everybody.

||Welcome to this tutorial on '''Control Execution''' in '''KTurtle'''.

||00:10

||In this tutorial, we will learn:  

|| 'while' loop  and

||'for' loop.

|| 00:17

||To record this tutorial, I am using:

||00:32

||We assume that you have basic working knowledge of '''Kturtle'''.  

||If not, for relevant tutorials, please visit our website: http://spoken-tutorial.org

||00:45

||Let's open a new '''KTurtle Application'''.

||Click on '''Dash  home'''.  

||In the '''Search bar''', type: "kturtle".

||Click on the option. '''KTurtle Application''' opens.

||00:59

||Let me first explain about what is '''control execution'''.

||01:05

||'''Control execution''' is controlling the flow of a program.  

||Different conditions are used to control program execution.

||01:16

||'''Loop''' is a '''block''' of code,  executed repeatedly till a certain '''condition''' is satisfied.

||e.g. “while” loop and  “for” loop.

||01:30

||Let's begin the tutorial with '''“while”''' loop.

||01:34

||In  the '''“while'''” loop, the code inside the loop repeats till '''Boolean''' evaluates to "false".

||01:42

||Let me explain the structure of '''“while”''' loop:

||01:56

||I already have the code in a text-editor.

||01:59

||Let me copy the program from text editor and paste it into '''KTurtle''' editor.

||Please pause the tutorial here and type the program into your '''KTurtle''' editor.

||02:18

||Let me zoom into the program text, it may possibly be a little blurred.

||02:25

||Let me explain the code.

||02:27

||'#' hyash sign comments a line written after it.  

||It means, this line will not be executed while running the program.

||02:38

||'''reset''' command sets '''“Turtle'''” to its '''default''' position.

||02:43

||'''$x=0''' initializes the value of variable 'x' to zero.

||02:52

||Message in a program is given within double quotes after the keyword  "message". '''“message”''' command takes '''string''' as input.  

||It shows a pop-up dialog-box containing text from the '''string'''.  

||03:11

||'''while $x<30''' checks the “while” condition,  

||03:17

||'''$x=$x+3''' increments the value of  variable $x by 3.

||03:27

||'''fontsize 15 ''' sets the font-size used by '''print''' command.  

||'''fontsize''' takes number as input, set in pixels.

||03:42

||'''forward 20''' commands '''Turtle''' to move 20 steps forward on the canvas.

||03:52

||'''print $x''' displays the value of variable 'x' on the canvas.

||04:01

||Let me click on the '''Run''' button to '''run''' the program.

||A message dialog-box pops up. Let me click '''OK'''.

||04:11

||Multiples of 3, from 3 to 30, are displayed on the canvas.  

||'''Turtle''' moves 20 steps forward on the canvas.  

||04:22

||Let's next work with “for” loop.

||04:26

||“for” loop is a counting loop.

||Every time  the code inside '''for''' loop is executed,

||variable value is incremented till it reaches the end value.

||04:41

||Let me explain the structure of “for” loop.

||'''for variable = start number to end number { Statement}'''

||04:55

||Let me clear the current program.

||Let me type "clear" command and '''run''' to clean the canvas.

||05:05

||Let me copy the program from text-editor and paste it into KTurtle editor.

||Please pause the tutorial here and type the program into your KTurtle editor.

|| Resume the tutorial after typing the program.

||05:25

||Let me zoom into the program text, it may possibly be a little blurred.

||05:32

||Let me explain the program.

||05:34

||'#' hyash sign comments a line written after it.

||05:39

||'''reset''' command sets '''Turtle''' to its '''default''' position.

||05:44

||'''$r=0''' initializes the value of variable 'r' to zero.

||05:52

||'''for $x= 1 to 15''' checks “for” condition  from 1 to 15.

||06:01

||'''$r=$x*($x+1)/2''' calculates the value of variable 'r'.

||06:12

||'''fontsize 18''' sets the font-size used by '''print''' command.  

||06:19

||'''print $r''' displays the value of  variable 'r'  on the canvas.  

||06:26

||'''forward 15''' commands '''Turtle''' to moves 15 steps forward on the canvas.

||06:34

||'''go 10,250''' commands '''Turtle''' to go 10 pixels from left of canvas and 250 pixels from top of canvas.

||06:48

||“Turtle” displays all print commands without any time gap.

||“Wait 2” command makes Turtle to wait for 2 seconds, before executing next command.

||07:04

||“print” command displays the '''string''' within double quotes and also displays variable '$r'.

||07:13

||Let me click on the ''' Run''' button to '''run''' the program.

||A series of sum of first 15 natural numbers and  "Sum of first 15 natural numbers" are displayed on the canvas.

||'''Turtle''' moves 15 steps forward on the canvas.

||07:32

||With this, we come to the end of this tutorial.  

||07:37

||Let us summarize.

||In this tutorial, we have learned to use  

|| “while” loop and “for”  loop.

||07:47

||As an assignment, I would like you to write programs to evaluate-

||Multiples of 2 using “while” loop.

||Multiplication table of a number using “for” loop.

||08:03

||Watch the video available at  this URL: http://spoken-tutorial.org/What_is_a_Spoken-Tutorial  

||It summarizes the Spoken Tutorial project.  

||If you do not have good bandwidth, you can download and watch it.  

||The Spoken Tutorial project team:

|| Conducts workshops using spoken tutorials.  

|| Gives certificates to those who pass an online test.  

||For more details, please write to: contact@spoken-tutorial.org

||08:36

||'''Spoken Tutorial''' project is a part of the '''Talk to a Teacher''' project.  

||It is supported by the National Mission on Education through ICT, MHRD, Government of India.  

||More information on this mission is available at this link: http://spoken-tutorial.org/NMEICT-Intro  

||This is Madhuri Ganpathi from '''IIT Bombay''', signing off. Thank you  for joining.