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

From Script | Spoken-Tutorial
Jump to: navigation, search
Line 5: Line 5:
 
||Slide Number 1
 
||Slide Number 1
 
||
 
||
−
 
−
 
 
Hello Everybody.
 
Hello Everybody.
  
Line 57: Line 55:
 
||Slide Number 5
 
||Slide Number 5
  
−
Control execution
+
'''Control execution'''
 
||Control execution is controlling the flow of a program.  
 
||Control execution is controlling the flow of a program.  
  
Line 64: Line 62:
 
||Slide Number 6
 
||Slide Number 6
  
−
Loop
+
'''Loop'''
 
||Loop is a block of code is executed repeatedly untill a certain condition is satisfied.
 
||Loop is a block of code is executed repeatedly untill a certain condition is satisfied.
 
Eg. '''“while”''' loop and  '''“for”''' loop
 
Eg. '''“while”''' loop and  '''“for”''' loop
Line 73: Line 71:
 
||Slide Number 7
 
||Slide Number 7
  
−
“while”  loop
+
'''“while”  loop'''
 
||In  the '''“while'''” loop, the code inside the loop repeats till '''boolean''' evaluates to 'false'.
 
||In  the '''“while'''” loop, the code inside the loop repeats till '''boolean''' evaluates to 'false'.
 
|-
 
|-
 
||Slide Number 8
 
||Slide Number 8
  
−
Syntax of  “while” loop
+
'''Syntax of  “while” loop'''
 
||Let me explain the structure of '''“while”''' loop.
 
||Let me explain the structure of '''“while”''' loop.
−
'''while loop condition {  
+
 
−
   do something  
+
'''while loop condition''' {  
−
  with  loop increment variable
+
 
 +
   '''do something '''
 +
 
 +
'''with  loop increment variable
 
}'''
 
}'''
 
|-
 
|-
 
||
 
||
−
||
+
||I already have the code in a text editor.
−
 
+
−
I already have the code in a text editor.
+
 
|-
 
|-
 
||'''#program to print a series of multiples 3 upto 30'''
 
||'''#program to print a series of multiples 3 upto 30'''
Line 127: Line 126:
 
||'''reset''' command sets '''“Turtle'''” to its '''default''' position.
 
||'''reset''' command sets '''“Turtle'''” to its '''default''' position.
 
|-
 
|-
−
||Highlight $x
+
||Highlight '''$x'''
 
||'''$x=0''' initialises the value of variable x to zero.
 
||'''$x=0''' initialises the value of variable x to zero.
 
|-
 
|-
 
||Highlight '''message" "'''
 
||Highlight '''message" "'''
−
||Message in a program is given within double quotes after the keyword  message " "   
+
||Message in a program is given within double quotes after the '''keyword''' '''message " "'''  
−
'''“message”''' command takes “string” as input.  
+
'''“message”''' command takes '''“string”''' as input.  
 
It shows a pop-up dialog box containing text from the string.  
 
It shows a pop-up dialog box containing text from the string.  
 
|-
 
|-
Line 162: Line 161:
 
|-
 
|-
 
||
 
||
−
||
+
||Let's next work with '''“for”''' loop
−
Let's next work with '''“for”''' loop
+
 
|-
 
|-
 
||Slide Number  9
 
||Slide Number  9
−
"for" loop
+
 
 +
'''"for" loop'''
 
||“for” loop is a counting loop.
 
||“for” loop is a counting loop.
  
−
Every time  the code inside “for” loop is executed,
+
Every time  the code inside '''“for”''' loop is executed,
  
 
variable value is incremented, till it reaches  the end value.
 
variable value is incremented, till it reaches  the end value.
Line 175: Line 174:
 
||Slide Number 10
 
||Slide Number 10
  
−
Syntax of “for” loop
+
'''Syntax of “for” loop'''
−
||Let me explain the structure of “for” loop.
+
||Let me explain the structure of '''“for”''' loop.
  
 
'''for variable = start number to end number  { Statement}'''
 
'''for variable = start number to end number  { Statement}'''
 
|-
 
|-
−
||Clear the editor and canvas
+
||'''Clear the editor and canvas'''
 
||Let me clear the current program.
 
||Let me clear the current program.
  
Line 201: Line 200:
 
'''forward 15'''
 
'''forward 15'''
 
}
 
}
 +
 
'''go 10,250''
 
'''go 10,250''
 +
 
'''wait 2'''
 
'''wait 2'''
 +
 
'''print "Sum of first 15 natural numbers ="+$r'''
 
'''print "Sum of first 15 natural numbers ="+$r'''
 
||Let me copy the program and paste it into KTurtle editor
 
||Let me copy the program and paste it into KTurtle editor
Line 238: Line 240:
 
||'''print $r''' displays the variable r.
 
||'''print $r''' displays the variable r.
 
|-
 
|-
−
||Highlight forward 15
+
||Highlight '''forward 15'''
−
||forward 15  moves Turtle 15 steps foward.
+
||'''forward 15''' moves '''Turtle''' 15 steps foward.
 
|-
 
|-
 
||Highlight '''go 10,250'''
 
||Highlight '''go 10,250'''
Line 254: Line 256:
 
||Let me click the '''“ Run”''' button to run the program.
 
||Let me click the '''“ Run”''' button to run the program.
 
A series of sum of first 15 numbers and  sum of first 15 natural numbers is displayed on the canvas.
 
A series of sum of first 15 numbers and  sum of first 15 natural numbers is displayed on the canvas.
 +
 
'''Turtle''' moves 15 steps forward.
 
'''Turtle''' moves 15 steps forward.
 
|-
 
|-

Revision as of 17:50, 26 December 2012

Slide Number 11 Summary
Visual Cue Narration
Slide Number 1

Hello Everybody.

Welcome to this tutorial on Control Execution in KTurtle

Slide Number 2

Learning Objectives

In this tutorial, we will learn

'while' loop and

'for' loop

Slide Number 3

System Requirement

To record this tutorial I am using,

Ubuntu Linux OS Version 12.04

KTurtle version 0.8.1 beta.

Slide Number 4

Pre-requisites

We assume that you have basic working knowledge of Kturtle.

If not,

for relevant tutorials, please visit our website. http://spoken-tutorial.org

Switch to KTurtle Application

Dash home >>Search bar appears>>

In the Search bar type KTurtle

Let's open a new KTurtle Application.

Click on Dash home. The Search bar appears.

In the Search bar, type KTurtle.

Click on the option. KTurtle Application opens.

Let me first explain about what is control execution.
Slide Number 5

Control execution

Control execution is controlling the flow of a program.

Different conditions are used to control program execution.

Slide Number 6

Loop

Loop is a block of code is executed repeatedly untill a certain condition is satisfied.

Eg. “while” loop and “for” loop

Let's begin the tutorial with “while” loop
Slide Number 7

“while” loop

In the “while” loop, the code inside the loop repeats till boolean evaluates to 'false'.
Slide Number 8

Syntax of “while” loop

Let me explain the structure of “while” loop.

while loop condition { 

 do something

with loop increment variable }

I already have the code in a text editor.
#program to print a series of multiples 3 upto 30

reset

$x=0

message"In while loop, code inside the loop repeats till boolean evaluates false"

while $x<30 {

$x=$x+3

fontsize 15

forward 20

print $x }

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. Please resume the turtorial after typing the program

Let me zoom into the program text it may possibly be a little blurred.
Let me explain the code.
Highlight # # sign comments a line written after it.

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

Highlight reset reset command sets “Turtle” to its default position.
Highlight $x $x=0 initialises the value of variable x to zero.
Highlight message" " 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.

Highlight while $x<30 while $x<30 checks the “while” condition.
Highlight $x=$x+3 $x=$x+3 increments the value of variable $x by 3
Highlight fontsize 15 fontsize 15 sets the font size used by print command.

Fontsize takes number as input, set in pixels.

Highlight forward 20 forward 20 commands “Turtle” to move 20 steps forward on the canvas.
Highlight print $x print $x displays the value of variable x on the canvas.
Run the program Let me click on the “Run” button to run the program.

A message dialog box pops up. Let me click OK.

Run the program Multiples of 3 from 3 to 30 are displayed on the canvas.

“Turtle” moves 20 steps forward on the canvas.

Let's next work with “for” loop
Slide Number 9

"for" loop

“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.

Slide Number 10

Syntax of “for” loop

Let me explain the structure of “for” loop.

for variable = start number to end number { Statement}

Clear the editor and canvas Let me clear the current program.

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

#program print to sum of first 15 natural numbers

reset'

$r=0

for $x= 1 to 15{

$r=$x*($x+1)/2

fontsize 18

print $r

forward 15 }

'go 10,250

wait 2

print "Sum of first 15 natural numbers ="+$r

Let me copy the program and paste it into KTurtle editor


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

Please resume the turtorial after typing the program.

Let me zoom into the program text it may possibly be a little blurred.
Let me explain the code.
Highlight # # sign comments a line written after it.
Highlight reset reset command sets “Turtle” to default position.
Highlight $r=0 $r=0 initialises the value of variable r to zero.
Highlight for $x= 1 to 15 for $x= 1 to 15 checks “for” condition from 1 to 15.
Highlight $r=$x*($x+1)/2 $r=$x*($x+1)/2 calculates the value of variable r.
Highlight fontsize 18 fontsize 18 sets the font size used by print command.
Highlight print $r print $r displays the variable r.
Highlight forward 15 forward 15 moves Turtle 15 steps foward.
Highlight go 10,250 go 10,250 commands Turtle to go 10 pixels from left of canvas and 250 pixels from top of canvas.
Highlight wait 2 “Turtle” displays all print commands without any time gap.

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

print "Sum of first 15 natural numbers ="+$r “print” command displays the “string” within double quotes and also displays variable $r.
Run the program Let me click the “ Run” button to run the program.

A series of sum of first 15 numbers and sum of first 15 natural numbers is displayed on the canvas.

Turtle moves 15 steps forward.

With this we come to end of this tutorial.
Let us summarize.

In this tutorial we have learnt to use,

  • “while” loop and
  • “for” loop
Slide Number 12

Assignment

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
Slide number 11 Acknowledgement

Watch the video available at this URL

http://spoken-tutorial.org/What is a Spoken Tutorial

It summarises the Spoken Tutorial project

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

Slide Number 13 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

Slide number 13 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

Contributors and Content Editors

Madhurig

Retrieved from "https://script.spoken-tutorial.org/index.php?title=KTurtle/C3/Control-Execution/English&oldid=2124"