KTurtle/C2/Grammar-of-TurtleScript/English
| Visual Cue | Narration |
|---|---|
| Slide Number 1
Title slide |
Hello everybody.
Welcome to this tutorial on Grammar of TurtleScript in KTurtle. |
| Slide Number 2
Learning Objectives |
In this tutorial, we will learn
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| 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. |
| Switch to KTurtle Application
Dash home >>In the Search bar type KTurtle click on the KTurtle icon. |
Let's open a new KTurtle Application.
Click on Dash home. In the Search bar, type KTurtle. Click on the KTurtle icon. |
| Press CTRL+ALT+T >> open the Terminal
>>type kTurtle >>press enter to open |
We can also open KTurtle Application from the Terminal.
Press CTRL+ALT+T simultaneously to open the Terminal. Type KTurtle and press enter KTurtle. Application opens |
| Slide Number 5
Turtle Script |
First I will explain about TurtleScript
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| Slide Number 6
Grammar of TurtleScript |
Grammar of TurtleScript in KTurtle includes-
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| Slide Number 7
Numbers |
Now we will see where to store numbers
Numbers can be stored in
|
| Zoom text | I will zoom the program text for clear view. |
| Switch to KTurtle window | First let's look at variables.
Variables are words that start with a ‘$’, for example $a. In the editor they are highlighted with purple. Using the assignment, equal to (=), a variable is given its content. Variables can contain numbers $a=100. strings $a=hello or boolean values that is true or false $a=true Variable keeps the content until program finishes execution or until it is reassigned to something else. You can use variables, once assigned, just as if they are their content. |
| For example, consider the code typed in the editor.
$a = 2004 $b = 25 print $a + $b | |
| Variable 'a' is assigned a value 2004.
Variable 'b' is assigned a value 25 print command commands Turtle to write something on the canvas. print command takes numbers and strings as input. print $a + $b commands Turtle to add two values and display them on the canvas. | |
| Run the code | Let's Run the code slow speed.
Value 2029 is displayed on the canvas |
| Slide Number 8
Mathematical operators |
Let us next see the Mathematical Operators.
Mathematical operators include,
|
| I already have a program in a text editor. | |
|
reset canvassize 200,200 $add = 1 + 1 $subtract = 20 – 5 $multiply = 15 * 2 $divide = 30 /30 go 10,10 print $add go 50,50 print $subtract go 100,100 print $multiply go 175,175 print $divide go 0,0 |
I will copy the code from text editor and paste it into KTurtle editor.
Pause the tutorial and type the program into KTurtle editor. Resume the tutorial after typing the program |
| I will Explain the code now | |
| Highlight reset | “reset” command sets Turtle to its default position |
| Highlight canvassize 200,200 | canvassize 200,200 fix the width and height of the canvas to 200 pixels each. |
| Highlight $add = 1 + 1 | value 1+1 is assigned to the variable $add, |
| Highlight $subtract = 20 – 5 | Value 20-5 is assigned to variable $subtract, |
| Highlight $multiply = 15 * 2 | value 15 * 2 is be assigned to the variable $multiply. |
| Highlight $divide = 30 /30 | 30/30 is assigned to the variable $divide. |
| Highlight go 10,10 | go 10,10 commands to Turtle to go 10 pixels left of canvas and 10 pixels from top of canvas |
| Run code
Point to the values |
Let us now run this code in slow speed
Command which is getting executed is highlighted in the editor. Turtle displays the values on the canvas at the specified positions. |
| Let us consider a simple example for using the comparison operator .
Type the commands being shown on the screen. | |
| zoom text | I will zoom the text to have clear view |
| Switch to Kturtle Window | $answer = 10 > 3
print $answer Here 10 is compared to 3 with the ’greater than’ operator. The result of this comparison, the boolean value true is stored in the variable $answer and the value true is displayed. |
| Run the code | Let's run this code
Turtle has displayed Boolean value true on the canvas. |
| Slide Number 9
Strings |
Now lets see how Strings work in this application –
|
| clear code | I will clear the current code from editor. |
| Example of string | For example:I am typing the print command followed by a string,
“Hello”. We See that the string is highlighted in Red color. |
| Run code | When I run this piece of code, the turtle displays the string on the canvas. |
| Boolean Values | Next I will explain about Boolean values.
There are only two boolean values: true and false. |
| For example Let's type the code
`if-else' Condition $answer = 7<5 print $answer Boolean value false is displayed on the canvas. Boolean value false is assigned to variable $answer because 7 is larger than 5 | |
| “if-else” conditon. | Let's next learn about “if-else” conditon.
‘if’ condition is executed only if the boolean value evaluates ‘true’ ‘else’ condition is executed only if the ‘if’ condition is ‘false’ . |
| I already have a program in a text editor. | |
| reset
$x=4 if $x>5 { print $x print “is greater than five” } else { print $x print “is smaller than six” } go 0,0 |
I will copy the code from text editor and paste it into KTurtle editor.
Pause the tutorial and type the program into KTurtle editor. Resume the tutorial after typing the program |
| This code compares numbers 4 , 5 and 6 and displays the results accordingly. | |
| Run code | Let me now run this code.
Turtle has compared the variables 4 and 5. and displayed the result 4 is smaller than 6 on the canvas . |
| With this we come to the end of this tutorial.
Let's summarize. | |
| Slide Number 10
Summary |
In this tutorial, we have learnt about
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| Slide Number 11
Assignment |
Now to the assignment part.
Solve an equation using
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| Slide Number 12
Assignment |
To solve the assignment
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| Slide number 13
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 14 | 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 15 | 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 ] Script is contributed by ITfC Bangaluru. This is Madhuri Ganpathi from IIT Bombay signing off Thank you for joining. |