- Table of Contents
- Course Home
- Assignments
- Peer Instruction (Instructor)
- Peer Instruction (Student)
- Change Course
- Instructor's Page
- Progress Page
- Edit Profile
- Change Password
- Scratch ActiveCode
- Scratch Activecode
- Instructors Guide
- About Runestone
- Report A Problem
- 3.1 Unit Overview
- 3.2 Paint Pot Tutorial
- 3.3 Representing Images
- 3.4 Paint Pot Projects
- 3.5 Paint Pot Refactoring and Procedural Abstraction
- 3.6 Error Detection
- 3.7 Parity Error Checking (optional)
- 3.8 Map Tour Tutorial
- 3.9 Map Tour With TinyDB
- 3.10 Impacts of CS Electronic Documents
- 3.11 Wrap Up
- 3.5. Paint Pot Refactoring and Procedural Abstraction" data-toggle="tooltip">
- 3.7. Parity Error Checking (optional)' data-toggle="tooltip" >
3.6. Error Detection ¶
Time estimate: 45 minutes, 3.6.1. introduction and goals ¶.
As we have learned from Blown to Bits , "everything is bits" -- i.e., all data are represented as binary 0s and 1s.
Suppose your bank is doing an electronic funds transfer and one of the bits involved switches from 0 to 1 or vice versa? This is known as a flipped bit . It could happen because of an error during transmission or while the data is being written to a disk drive. And the error could make a significant difference. For example, if we use only 8 bits then flipping the leftmost bit 00000001 to 10000001 changes the value from $1.00 to $129.00. But if we used 16 bits, then flipping the leftmost bit of 0000000000000001 to 1000000000000001 changes the value from $1.00 to $32,769.00.
When something like this happens would it be possible to detect the error? In this video based on this Computer Science Unplugged project, you'll see a card trick that shows that it is possible to detect when a bit is flipped. In the video, the face-up and face-down cards are analogous to 1s and 0s.
3.6.2. Learning Activities ¶
- YouTube video
- POGIL worksheet
POGIL Activity for the Classroom (30 minutes)
Error detection: critical thinking questions.
For this activity, each group should have 36 playing cards (or 25 for a smaller square) or use this virtual deck or use the widget above. For a regular card deck you can use face-up/face-down to represent 0/1. A satisfactory outcome for this activity is that the team can successfully demonstrate the trick to the class. That means, someone will lay out a 5x5 array of cards randomly. Then a member of the team will layout the 6th row and column and will successfully identify the flipped card when some from the class secretly flips a single card.
- In the video, are the 6th row and 6th column being laid out in a truly random way or is some kind of rule or algorithm being used? If so, what's the rule?
- HINT: Count the number of face cards in each row and column? What pattern or rule do you see if you do that?
- Practice: Everyone on the team should practice the "trick" using the widgets or the deck of cards.
- ( Portfolio ) What is the "trick"? Of course, it's not really a trick. It's an algorithm. So, describe an algorithm in pseudocode that solves the problem of identifying the flipped card.
- ( Portfolio )The card "trick" shows that it is always possible to identify the card that was flipped as long as only one card was flipped. Would it be possible always to determine if an error occurred if two cards were flipped? Experiment with the cards or widgets to help answer this question.
- In this case, the 25 original cards (bits) are data and the 11 additional bits are for error detection, meaning that 25/36 = 69% of the bits are data and 31% are redundant bits used for error detection. Suppose the original array was 3x3. How many error detection bits would you need in that case and what percentage of the total bits would now be data bits?
Parity Bit Error Detection
3.6.3. summary ¶, 3.6.4. still curious ¶.
What about detecting errors that involve more than 1 bit? Is it possible to not only detect an error but to automatically correct it? The answers to these questions is 'Yes' and 'Yes.'
If you want to learn more about this topic, here are a couple of reading suggestions:
- Mobile CSP Lesson 3.7 Parity Error Checking
- Parity bit .
- Nice video demonstration of error correction .
- Error detection and correction .
3.6.5. Self-Check ¶
Here is a table of some of the technical terms we've introduced in this lesson. Hover over the terms to review the definitions.
Check Your Understanding
Complete the following self-check exercises.
- The bit in row 4 column 4.
- The bit in row 4 column 3.
- Don’t worry, it’s hard! Let’s go back and try it again.
- The bit in row 1 column 2.
- The bit in row 2 column 2.
- Try asking a classmate for advice—s/he may be able to explain/suggest some ideas or recommend some strategies.
3.6.6. Reflection: For Your Portfolio ¶
Answer the following portfolio reflection questions as directed by your instructor. Questions are also available in this Google Doc where you may use File/Make a Copy to make your own editable copy.
IMAGES
VIDEO
COMMENTS
Map Tour Tutorial (video or handout) 3.8.1. ... Portfolio Reflection Questions Solutions; Assessment Opportunities. You can examine students' work on the interactive exercise and their reflection portfolio entries to assess their progress on the following learning objectives. If students are able to do what is listed there, they are ready to ...
Portfolio Reflection Questions. Make a copy of this document in your Portfolio Assignments folder and answer these questions in the spaces below. Once complete, turn in this assignment according to the steps given by your teacher. 3.8 Map Tour Tutorial Curriculum Page. Answer the following questions: 1. How are lists used in this app?
Reflections. 2.02 I Have a Dream Part 1. 2.03 The Internet and The Cloud. 2.04 I Have a Dream Part 2. 2.05 Mobile Apps and Mobile Devices ... 3.8 Map tour tutorial. 5.3 Search Algorithms. 5.4 Sorting Algorithms. 5.5 Caesar Cipher App (NEW) 5.6 Debugging Caesar Cipher (NEW) 5.7 Analyzing Algorithms. 5.8 Limits of Algorithms. Sitemap. Reflections ...
View Isaiah Angulo - 3.08 and 3.09 Map Tour Tutorial Reflection.docx from MATH 11A at Vallivue High School. 3.8/3.9 Map Tour Tutorial Curriculum Page Answer the following questions: 1. How are lists
Table of Contents; Course Home; Assignments; Peer Instruction (Instructor) Peer Instruction (Student) Change Course; Instructor's Page; Progress Page; Edit Profile; Change Passwor
1. What is the list picker component? How was it used in this app? -The list picker component allows you to create a list of options that can be selected. We used it in the Map Tour app by creating...
Mobile CSP Map Tour Tutorial (Revised)
View Copy of 3.8_3.9 Map Tour Reflections.docx from COMPUTER SCI 237 at Athens Drive High. 3.8 Map Tour Tutorial Curriculum Page Answer the following questions: 1. Why is a list a useful data
Answer The first enhancements makes it so that there are different types of Map Types you can pick and choose from. The list gives options so you can use them. The zoom slider allows so you can zoom into the map easily with the slider UI. The location button when clicked gives a coordinates from where your location is, using the GPS. But the GPS only works when outside, not on the inside.
3.08 Map Tour Tutorial. 3.09 Map Tour with GPS and TinyDB. Unit 04 Exploring Computing. 4.02 Turn Off Lights Tutorial. 4.03 Turn Lights Off Projects. 4.04 Logo 1. 4.05 Coin Flip Simulation Tutorial. ... Answer the following questions: How is the ListPicker component used in this app? Answer
Portfolio Reflection Questions. Make a copy of this document in your Portfolio Assignments folder and answer these questions in the spaces below. Once complete, turn in this assignment according to the steps given by your teacher. 3.8 Map Tour Tutorial Curriculum Page. Answer the following questions: 1. How are lists used in this app?
Portfolio Reflection Questions. Make a copy . of this document in your Portfolio Assignments folder and answer these questions in the spaces below. Once complete, turn in this assignment according to the steps given by your teacher. 3.8 Map Tour Tutorial Curriculum Page. Answer the following questions: 1. How are lists used in this app?
Wrap Up — Mobile CSP. 3.11. Wrap Up ¶. Congratulations on making it to the end of Unit 3! 3.11.1. MIT App Inventor Drills ¶. Test and improve your coding knowledge and skills with some additional exercises. For this unit there are three sets of Drills. Setters, Getters, and Math -- drills that use MIT App Inventor's variable and setter and ...
GPS is a system of satellites that orbit earth that send messages to receivers. Once the receiver finds its distance from four or more satellites, it knows where you are located. 3.8 Map Tour Tutorial (REVISED) This allows the user to switch between a map with roads, an aerial view/overview of the area, or the terrain.
3.10 Map Tour Tutorial. 3.2 Paint pot. 3.3 Creating Graphics and Images bit by bit. ... 3.10 Map Tour Tutorial. Create a page named Map Tour under the Reflections category of your portfolio and answer the following questions:
3.9.1. Introduction and Goals ¶. In this lesson we will extend the Map Tour App by adding two new features: Adding Destinations to the Tour. We will allow users to click on the map to add new destinations to the map tour. Data Persistence. We will incorporate TinyDB, MIT App Inventor's database component, which will enable the app to save new ...
Includes: 3.1. Unit Overview 3.2. Paint Pot Tutorial 3.3. Representing Images 3.4. Paint Pot Projects 3.5. Paint Pot Refactoring and Procedural Abstraction…
3.8 Map Tour Tutorial; 3.9 Map Tour with TinyDB; ... (10 minutes): Have students complete the first two questions of their portfolio reflections in class and tell them to complete the last question for homework. AP Classroom. The College Board's AP Classroom provides a question bank and Topic Questions. You may create a formative assessment ...
View U3L8_MapTour.docx from BIOL 1107 at University Of Connecticut. Introduction to CS Principles Unit 3.8 Map Tour Lesson Link: Where is App Inventor? Video #1: Video
Reflections. 2.02 I Have a Dream Part 1. 2.03 The Internet and The Cloud. ... 2.08 Abstraction 1. 2.10 Hardware Abstractions: Logic Gates. 2.11 BB: The Digital Explosion. 2.12 Wrap Up. 3.10 Map Tour Tutorial. 3.11 Electronic Documents. 3.12 Wrap Up (DRILLS) 3.2 Paint Pot Tutorial. 3.3 Representing Images. ... Edward Snowden Questions And Vocab.
3.8 Map Tour Tutorial; 3.9 Map Tour With TinyDB; 3.10 Impacts of CS Electronic Documents; 3.11 Wrap Up ... Records all answers & questions, and provides the team's reflection to team and instructor. Process Analyst: Considers how the team could work and learn more effectively.