Week 26 - Selections and loops, MOD operator

CLASS OBJECTIVE

Reinforce the use of REPETIR and SI_ENTONCES commands by creating a new algorithm in PSeInt, but this time using a flowchart as a visual support. This new algorithm's purpose is to analyze a number to determine whether is a prime number or not.

INTRODUCTION

Today you're going to create a new algorithm to determine prime numbers. You already know the commands and the programming structures, except for the MOD operator, but you'll find it's a very simple mathematic operator related with division.

MOD OPERATOR

You're going to use a new operator, its name is MOD and the symbol that represent it is %. 

In this case, it doesn't mean "percentage", in this case means REMAINDER of a division.

For our practical purpouses, you must know that every time you get zero as a remainder it means you found an exact divisor.

Try the next algorithm in PSeInt:

If you try 42 as dividend and 8 as divisor the remainder will be 2.

If you try 21 as dividend and 7 as divisor the remainder will be 0. It is an exact divisor.

This two numbers might have many exact divisors but, what about prime numbers like 23?

Prime numbers just have two divisors: one and itself.

CLASS ACTIVITY 

• Create a new file in PseInt
• Start naming the algorithm as Números_primos, without spaces, for the algorithm and the file. Remember the difference between the algorithm name and the file name, in which you can use spaces. 
• Now, you're going to use the next flowchart to create the algorithm in PSeInt. Remember, you have to type commands and operators, or you can click on the left and right panels instead to insert then in the algorithm.

After you finish, press the "play" button to test it. Obviously, it must tell you if a given number is prime or not.

Save the file and, before you turn it in,  press the "flowchart" button. Does it look like the image above?

CLASS NOTES

Write down in your notebook the title of the class, the objective and follow the instruction.

• Write down the algorithm code from PSeInt in your notebook and explain, using your own words, what does every code line do, from the first until the last.

Show your answers to your teacher.

Week 25 - Selections and loops practice

CLASS OBJECTIVE

Reinforce the use of the SI ENTONCES and the REPETIR commands by creating algorithms by yourself, just knowing the final result of the program.

INTRODUCTION

Last class you learned the use of SI ENTONCES to create multiple paths in an algorithm. By the analysis of  variables content the procedure can change and produce different outcomes.

Today you'll create by your self a program to analyze a word's length, obviously using SI ENTONCES, and after this you'll adapt the program to be repeated until the user chooses to exit.

Remember, you won't get any help from your teacher.

ACTIVITY 1

Remember, the activity's purpose is that you create the algorithm all by yourself so, you'll receive a just a couple of guidelines.

1. Name the algorithm LONGITUD_DE_TEXTO
2. Declare 1 variable to save a word
3. Ask the user for a word (or phrase) to save it into the variable
4. Tell the user if the word's length has more than 15 characters (tip: you'll also have to use LONGITUD() function)
• Otherwise, tell the user the word is smaller than 15 characters.

Look at the examples:

ACTIVITY 2

Now you have to add a loop to your first algorithm to repeat over and over until the user decides to finish it.

1. Declare another variable to save a text
2. You'll have to add the REPETIR/HASTA QUE command to wrap the last procedure.
3. Inside the loop you'll have to ask the user if he wants to "try with another word", receive his answer and save it to the new variable.
4. The algorithm will continue until the user types some letter different to the "s" letter.

Look at the examples:

If you need one last resource to finish your algorithm, look at the next flowchart:

CLASS NOTES

Write down in your notebook the title of the class, the objective and follow the instruction.

1. What kind of data type you choose to save the user's incoming words? why?
2. What does the LONGITUD() function do?
3. Is it possible to indicate the "different to" comparison symbol instead of "equal to"? How?

Show your answers to your teacher.

Week 24 - Combined Loops and selections

 CLASS OBJECTIVE

Relate PseInt Loops and Selections, from the last class, into some new proyects where we can combine the use of both resources

ACTIVITY 1

Last class we created two algorithms, the fist using "Selections" and the second using a "Loop". Today we'll start with a combined algorithm.

Open PseInt and type the next algorithm. Save the file using the same algorithm's name, into the "Documentos" folder.

Execute the algorithm, test it and personalize it, try to understand it deeply. After this, you'll add comments in every code line explaing what does it do. To do this, use the double slash simbol.

Watch the example in the image below.

Save your file once again and up load it to Classroom.

ACTIVITY 2

Now, this is your turn to create an algorith completely by yourself, in this case, a simple game. Use the paramethers listed below.

• Use the name Guess_number for the algorithm and the file.
• User will have only 4 tries. After the fourth, the program ends.
• The hidden number must be in between 1 and 10 (including them)
• Look at the last algorithm and make the necessary adjustments.

Upload the file to the same Week 24 post in Classroom.

CLASS NOTES

As always, start writting the class title and objective

•     Just draw the game flowchart in your notebook

Week 23 - Selections and Loops using PSeInt

 CLASS OBJECTIVE

Create in PSeInt an algorithm that uses selections and loops (programming structures) by analyzing a flow chart that describes every step of process.

INTRODUCTION

Any programming language must have the selections and loops programming structures because ane procedure has to make decisions or to repeat procedures. Obviously PSeInt has this two resources among others. The name of this two command are: SI-ENTONCES and  REPETIR

 

SI-ENTONCES

I'm sure it'll be difficult to understand the "written" version of this commands, but I'm sure you'll get use to it. Look at the SI-ENTONCES examples:

In the flowchart it looks like:

Indentation 

As you can see, it's not as difficult as it looked. To keep it simple you must always use the indentation to show the inner step of the procedure on the right.

ACTIVITY 1

Now open PseInt and type the next algorithm. What does it do?

REPETIR

REPETIR is a command to create a loop, in other words, the repetition of a list of actions. In the next example, a message will be shown over and over until the variable div decreases until cero.

Now in a flowchart look:

Never forget to use the indentation to identify the procedures in the selections or in the loops structures.

ACTIVITY 2

Now open PseInt once again and type the next algorithm. What does it do? Have you done something like this before?

Upload the two files (SI_ENTONCES y REPETIR_HASTA QUE) to the Classroom post.

CLASS NOTES

Write down in your notebook the title of this class and the objective. Using Raptor symbols, draw the next flow charts.

• Draw the flow chart for the Activity 1
• Draw the flow chart for the Activity 2

Show your answers to your teacher.

Week 22 - PseInt, Programming learning tool

CLASS OBJECTIVE

To know for the first time the programming learning tool named PSeInt and its working environment by creating two algorithms using different data types: characters and floating point numbers.

INTRODUCTION

As you learned last class, before you start programming you have to know some basic rules of the programming languages: declare different variables types, the using of delimiters, the recongnition of sentences or code lines.

Today we'll start using PSeInt which is a very helpful tool to start learning programming languages. By the way, it works in spanish.

This is the PSeInt main window.

1. This is the tool bar. In here you'll find tools like the save, save as, new, do and undo buttons. There are also two very important buttons here, the execute and the flowchart buttons.
2. The main working area. This is where you're going to create the program by typing commands or operation names, right between the start and end algorithm points.
3. The list of the available operations for data processing. For example: the basic mathematical operators, comparison operators, character operators, etc.
4. The commands and programming structures. This is a helpful guide to remember how to interact with the user, how to analyze the information and how to use selections or loops in an algorithm.

To create an algorithm you'll have to type every sentence (code line) between "Algoritmo" and "Fin Algoritmo". Don't forget to name your program where the algorithm starts.

Variables

When using PSeInt, before you use variables you'll have to declare them. This means you have to reserve and name a memory space before you use it. How to do it? You´ll use the word "Definir", type the name and select data type.

• Caracter is used to save letters and some symbols.
• Entero is used to save integer numbers.
• Lógico is used to save "true" or "false" answers.
• Real is used to save decimal numbers.

There's only one way to learn how to use PSeInt, by creating programs.

ACTIVITY 1

Start naming the algorithm, its name will be Contador_de_caracteres. As you can see, you can´t use spaces.

Now try to type the next algorithm, I'm sure you'll have to correct some mistakes, it always happen the first time. For example, if you miss the semi-colon delimiter or the quotation marks PSeInt will inform you.

• Escribir and Leer are "well known for you" commands (reserved words), to show information or to ask for information to the user.
• Longitud is an operator to count letters in a string.

After you finish, press the "play" button to test it.

Save the file and, before you turn it in,  press the "flowchart" button. I hope it could be familiar for you.

ACTIVITY 2

For the second activity, you'll try to create the next by your self. 

The only different thing you'll need is a small arrow in the assignment formula. 

To get it, type <- (less than and dash)

Once again, after you finish, press the "play" button to test it.

Save the file and, before you turn it in,  press the "flowchart" button.

CLASS NOTES

Write down in your notebook the title of the class, the objective and answer the next questions.

• What does "declare variables" means?
• What are the four data types in PSeInt?
• Which of those were used in today's activities?
• What is the semicolon used for?
• What are the Quotation marks used for?
• How did you type the assignment arrow?

Show your answers to your teacher.

HOMEWORK

THIRD PERIOD COVER
To get started, you'll create the cover for Period 3, in no more than 10 minutes. The requirements are the following:

• Period III written in  large size font
• Technology III written below the period title
• Your name, list number and group
• A drawing allusive to Programming languages

Week 21 - Pseudocode practice

CLASS OBJECTIVE

Create and execute a program using pseudocode (algorithm written in your own words) to perform a specific task inside the classroom, so we can write our first program using words and statements.

To reinforce the concepts from our last class, today we'll begin creating our first programs. Before you start, there are a few key points and guidelines to understand.

• First, you need to know the goal of the task—what the program is supposed to accomplish.
• Next, take a sheet of paper and design the procedure, using program structures such as decision-making statements and loops, with a minimal set of instructions. Keep in mind that you should only include actions the program is capable of performing.
• Once you've completed your program, you won’t be running it yourself; another entity, the Interpreter, will handle its execution.

ACTIVITY

PHASE 1. PROGRAMMER

1. Pick a sheet of paper, select one of the next goals and write it on the paper as a title.
• Open/Close window. Select the windows by its number.
• Turn on/off the fan.
2. Now, write the pseudocode using natural English, but structured in a way that reflects programming logic. Use the next reserved words list:
• START
• END
• ACTIONS
• Step_forward
• Step_back
• Turn_left
• Turn_Right
• Switch_on
• Switch_off
• Open
• Close
• IF condition DO
• Action 1
  
• Action 2
• Action n
• ELSE
• Action 1
• Action 2
• Action n
• (LOOP) WHILE condition DO
• Action 1
• Action 2
• Action n
• (LOOP) REPEAT UNTIL
• Action 1
• Action 2
• Action n

1. You can stand up (respectfully) to test your program
2. Once it's finished, write your name and student number and give it to your teacher.

PHASE 2. INTERPRETER

To grade the pseudocodes, some students will take on the role of an Interpreter. This means they will follow the program’s instructions to evaluate its design.

• The teacher will call on students one by one to stand up and execute a randomly selected program.
• If the program doesn’t achieve the desired goal, the sheet will be returned to the programmer for corrections. 
• If it works as expected, the programmer will simply add their name.

CLASS NOTES

As usual, write down the class title, the class objective, and answer the following questions:

• Is this activity written in a programming language? Why or why not? What’s the difference?
• When writing the program, did you use statements and delimiters? Provide an example.
• Did you identify any reserved words? If so, name three of them.
• Were there any variables in this activity? Was any data necessary to complete the task? If so, list it.

Week 20- Programming Languajes Theory

 CLASS OBJECTIVE 

Establish the bases for the work of the next phase, whose main topic will be the Programming Languages, through a research that will be resumed in plenary with brainstorming.

RESEARCH ACTIVITY

THEORY OF PROGRAMMING LANGUAGES
You'll research the following concepts on the Internet and later we will return them in plenary with brainstorming.

In Classroom you will receive a document to recover the investigated information .

• What does pseudocode mean?
• What are programming languages?
• What are statements in a programming language?
• What are delimiters in a programming language?
• What are "reserved words" in a programming language?
• What is a variable in programming?
• What are the data types in programming?

CLASS NOTES
As always, you will write down the title of this class, the objective and the above questions, but in this activity you will use your own words to describe what you understood about each concept.

HOMEWORK
Write down the answers to the following instructions in your notebook:

• Research on the Internet What is PseInt?
• Also look for an image of the main PseInt work screen and draw it.