Learn about why testing is needed, types of testing, types of test data and types of error. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 3.2: Testing Exam Board: OCR Specification: J277 Watch on YouTube : Purpose of Testing Types of Error Test Data The main purpose of testing is to ensure that a program works correctly no matter what input has been entered by the user. Other reasons to test a program include ensuring the user requirements have been met , errors have been removed and the program doesn't crash while running . Types of Testing Iterative Testing Iterative testing takes place during program development . The programmer develops a module , tests it and repeats this process until the module works as expected . Final Testing Final testing, also known as terminal testing , takes place after development and before the program is released to the end user. This testing takes place once all modules have been individually tested to ensure the whole program works as originally expected. Programming Errors Syntax Error Logical Error A syntax error is a mistake in the grammatical rules of the programming language , such as an incorrect spelling of a command word. A syntax error will prevent the program from being compiled and executed . Examples: Incorrect Spelling: pront ( "hello" ) Incorrect punctuation: print ( "hello" ( A logic error is a mistake made by the programmer - the program runs without crashing but will display the wrong output . Examples: Incorrect calculation: total = num1 - num2 print (total) Incorrect variable printed: age = 16 name = "Steve" print ( "Nice to meet you" , age) Test Data Test data is used to test whether a program is functioning correctly . It should cover a range of possible and incorrect inputs , each designed to prove a program works or to highlight any flaws . Four types of test data are: Normal data - Sensible data that the program should accept and be able to process . Boundary data - Data at the extreme boundary of any data ranges. Invalid data - Data of the correct data type that does not meet the validation rules (e.g. outside of the range). It should not be accepted . Erroneous data - Data of the wrong data type that the program cannot process and should not accept . Q uesto's Q uestions 3.2 - Testing: 1. Give 3 reasons why programs are tested . [ 3 ] 2. What is the difference between iterative and final testing ? [ 2 ] 3a. What is a syntax error ? Give an example . [ 2 ] 3b. What is a logical error ? Give an example . [ 2 ] 4. State and describe the four types of test data . [ 6 ] 3.1 - Defensive Design Theory Topics 4.1 - Boolean Logic

Learn how to create and use lists in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 8a - Using Lists Lists A list is a temporary data structure . Any changes made to the list while the program is running will not be saved the next time it is run . Data can be added to and removed from lists so they can change in size (unlike an array which is fixed and not used in Python). It is important to note that each data element in a list has an index so that it can be specifically referenced (to delete it for example) and that indexes start at 0 . A list of the rainbow colours in order would start at 0 like this: Creating & Printing Lists Lists use square brackets in Python. Separate list items with commas . Strings must use speech marks and integers do not use speech marks. people = [ "Alan" , "Jesse" , "Max" , "Jack" ] years = [ 2010, 2019, 2001, 2016 ] There are many different ways to print items from a list depending on how you want it to look . Print all items on one line Type the list name into a print command to output the complete list . Typing an asterisk * before the list name removes punctuation . cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print (cities) cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print (*cities) ['Shanghai', 'Sao Paolo', 'Bishkek', 'Asmara'] Shanghai Sao Paolo Bishkek Asmara Print each item on a separate line To print a list line-by-line use a for loop to cycle through each item. 'city ' is just a variable name and can be replaced with the traditional 'i ' or anything relevant to the context, such as 'colour ' in a list of colours or 'name ' in a list of people. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] for city in cities: print (city) Shanghai Sao Paolo Bishkek Asmara Print separated items on one line To print separated data elements on the same line then you can use the end command which defines what should go after each item . The example below uses slashes but end = " , " would add comma and space between each element. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] for city in cities: print (city, end = " / " ) Shanghai / Sao Paolo / Bishkek / Asmara / Print specific list items To print an element with a certain index , put the index in square brackets . But remember that the index starts at 0 not 1. cities = [ "Shanghai" , "Sao Paolo" , "Bishkek" , "Asmara" ] print ( "The first city is" , cities[0]) print (cities[2], "is the third city" ) The first city is Shanghai Bishkek is the third city Create a list of five different foods . Print all list items on one line . Then print each item on a different line . Finally print just the first and fifth items . Example solution: lettuce yoghurt tomato artichoke tuna lettuce yoghurt tomato artichoke tuna The first item is lettuce The fifth item is tuna Lists Task 1 (Five Foods ) Lists Task 2 (Four Numbers ) Create a list of four integer values . Print all list items on one line separated by colons . Example solutions: 345:123:932:758: 812:153:783:603: Add (Append / Insert) to a List Append items to the end of a list To add a new item to the end of a list use the .append() command. Write .append() after the name of your list, with the new data in brackets . pets = [ "dog" , "cat" , "hamster" ] pets.append( "rabbit" ) print (*pets) fillings = [ "ham" , "cheese" , "onion" ] extra = input ( "Enter another filling: " ) fillings.append(extra) print ( "Your sandwich:" , *fillings) dog cat hamster rabbit Enter another filling: lettuce Your sandwich: ham cheese onion lettuce Insert items to a specific index Use the insert command to place an item in a specific position within the list. Remember that Python counts from 0 so the medals example below puts "silver" as index 2 , which is actually the 3rd item . medals = [ "platinum" , "gold" , "bronze" ] medals.insert(2, "silver" ) print (*medals) names = [ "Stacy" , "Charli" , "Jasper" , "Tom" ] name = input ( "Enter a name: " ) position = int ( input ( "Enter an index: " )) names.insert(position,name) print (*names) platinum gold silver bronze Enter a name: Lena Enter an index: 0 Lena Stacy Charli Jasper Tom Enter a name: Pat Enter an index: 3 Stacy Charli Jasper Pat Tom Use a loop to add items to a list A for loop can be used to add a certain number of items to a list. A while loop can be used to keep adding values until a certain value (e.g. ' stop ' or ' end ') is input. animals = [ ] for i in range (4): animal = input ( "Enter an animal: " ) animals.append(animal) print ( "\nAnimals:" , *animals) animals = [ ] while True : animal = input ( "Enter an animal: " ) if animal == "stop" : break else : animals.append(animal) print ( "\nAnimals:" , *animals) Enter an animal: lion Enter an animal: horse Enter an animal: hyena Enter an animal: squirrel Animals: lion horse hyena squirrel Enter an animal: rhino Enter an animal: gazelle Enter an animal: deer Enter an animal: stop Animals: rhino gazelle deer Example solution: Lists Task 3 (Favourite Musicicans ) Create a list of three musicians or bands you like . Print the list . Then append two new bands using two inputs . Print the list again. Use the sandwich filling example for help. Musicians I like: Lana Del Rey Devon Cole Elly Duhé Enter another musician: Charli XCX Enter another musician: Kenya Grace Musicians I like: Lana Del Rey Devon Cole Elly Duhé Charli XCX Kenya Grace Lists Task 4 (Missing 7 ) Create a list of numbers in order from 1 to 10 but miss out 7 . Use the insert command to add 7 in the correct place . Print the list before and after you insert 7. Example solution: 1 2 3 4 5 6 8 9 10 1 2 3 4 5 6 7 8 9 10 Lists Task 5 ('Land' Countries ) Use a while True loop to input countries that end in 'land' until the word 'finish ' is input . Print the list at the end. Note: You do not need to check if the countries entered are correct. There are also more than four. Example solution: Enter a country ending in 'land': Iceland Enter a country ending in 'land': Poland Enter a country ending in 'land': Switzerland Enter a country ending in 'land': Thailand Enter a country ending in 'land': finish Country list: Iceland Poland Switzerland Thailand Delete (Remove/Pop) from a List Delete items with a specific value To delete data with a certain value use the .remove() command, with the value in brackets . trees = [ "fir" , "elm" , "oak" , "yew" ] trees.remove( "elm" ) print (*trees) fir oak yew trees = [ "fir" , "elm" , "oak" , "yew" ] tree = input ( "Select a tree to remove: " ) trees.remove(tree) print (*trees) Select a tree to remove: oak fir elm yew Delete items with a specific index To delete data in a specific position in your list use the .pop() command, with the position in the brackets . Remember that indexes start at 0 so .pop(0) removes the first item . Negative values start from the end of the list , so -1 is the final item and -2 is the second last item and so on. kitchen = [ "plate" , "cup" , "spoon" , "jug" ] kitchen.pop(0) print (*kitchen) kitchen = [ "plate" , "cup" , "spoon" , "jug" ] kitchen.pop(-2) print (*kitchen) kitchen = [ "plate" , "cup" , "spoon" , "jug" ] index = int ( input ( "Select an index: " )) kitchen.pop(index) print (*kitchen) cup spoon jug plate cup jug Select an index: 1 plate spoon jug Delete all items in a list To delete data in a list use the .clear() command. insects = [ "ant" , "bee" , "wasp" ] insects.clear() insects.append( "hornet" ) print (*insects) hornet Lists Task 6 (Day Off ) Example solution: Create a list with the five week days . Ask the user to input a weekday and remove that day from the list. Print the list. Which day do you want off? Tuesday Your new days of work: Monday Wednesday Thursday Friday Lists Task 7 (May and October ) Create a list with the twelve months in order . Delete May and then October using the pop command by referring to their indexes in the list. Print the list. Note: Be aware the index of each month after May will change when May is popped from the list. Example solution: January February March April June July August September November December Finding the Length of a List To find the length of a list use the len function. You can create a separate variable for the length (shown in the first example below) or use the len command directly (second example). states = [ "Maine" , "Utah" , "Ohio" , "Iowa" ] length = len (states) print ( "There are" , length , "states in the list." ) states = [ "Maine" , "Utah" , "Ohio" , "Iowa" ] print ( "There are" , len (states), "states in the list." ) There are 4 states in the list. Lists Task 8 (Q Words ) Use a while True loop to input words beginning with q until the word ' stop ' is entered. Then use len to find the length of the list and print this value. Note: You do not need to check if the entered words actually start with q. Example solution: Input a Q word: question Input a Q word: quick Input a Q word: quiet Input a Q word: quandry Input a Q word: stop You wrote 4 Q words! Cycle Through List Items A for loop can be used to cycle through each item in a list. The following examples present some ways that this may be used. This program uses a for loop to add a word (David) before each list item. davids = [ "Beckham" , "Attenborough" , "Schwimmer" , "Tennant" , "Lynch" ] for i in range (5): print ( "David" , davids[i]) David Beckham David Attenborough David Schwimmer David Tennant David Lynch An if statement can be used within a for loop to check the value of each item . The example below checks how many items are 'medium'. sizes = [ "small" , "medium" , "small" , "large" , "medium" , "small" ] count = 0 for i in range (6): if sizes[i] == "medium" : count = count + 1 print ( "There were" ,count, "medium choices." ) There were 2 medium choices. The program below uses a while loop to allow entries until 'stop ' is input then a for loop to check the value of each item . Because the final length of the list is not known when the program starts, the len command is used in the range of the for loop . sports = [] fcount = 0 rcount = 0 while True : option = input ( "Choose football or rugby: " ) sports.append(option) if option == "stop" : break for i in range ( len (sports)): if sports[i] == "football" : fcount = fcount + 1 elif sports[i] == "rugby" : rcount = rcount + 1 print ( "\nResults:" ,fcount, "people chose football and" ,rcount, "chose rugby." ) Choose football or rugby: rugby Choose football or rugby: rugby Choose football or rugby: football Choose football or rugby: rugby Choose football or rugby: football Choose football or rugby: stop Results: 2 people chose football and 3 chose rugby. Lists Task 9 (Over 25 ) Create a list with the following eight numbers: 13, 90, 23, 43, 55, 21, 78, 33 Use a for loop to cycle through the list and check if each item is over 25 . Use a count variable to increase by 1 if the number is over 25. At the end print how many numbers are over 25 - there are five . Example solution: 5 numbers are over 25. Lists Task 10 (Favourite Lesson ) Use a while True loop to keep inputting school subjects until ' done ' is entered. Keep a count of how many times ' Maths ' is entered. Print the total number of people who entered maths. Example solution: Enter a subject: English Enter a subject: Maths Enter a subject: Art Enter a subject: Maths Enter a subject: History Enter a subject: done There were 2 people who chose maths. Sorting Lists The .sort() command will sort elements in a list into alphabetical order (if a string ) or numerical order (if a number ). names = [ "Robb" , "Jon" , "Sansa" , "Arya" , "Bran" , "Rickon" ] print ( "Original:" , *names) names.sort() print ( "Sorted:" , *names) Original: Robb Jon Sansa Arya Bran Rickon Sorted: Arya Bran Jon Rickon Robb Sansa numbers = [56,98,23,12,45] numbers.sort() print (*numbers) 12 23 45 56 98 The .sort() command can be used to sort values in descending order by including reverse = True in the brackets. names = [ "Robb" , "Jon" , "Sansa" , "Arya" , "Bran" , "Rickon" ] print ( "Original:" , *names) names.sort(reverse = True ) print ( "Sorted:" , *names) Original: Robb Jon Sansa Arya Bran Rickon Sorted: Sansa Robb Rickon Jon Bran Arya numbers = [56,98,23,12,45] numbers.sort(reverse = True ) print (*numbers) 98 56 45 23 12 Lists Task 11 (Sorted Fruit ) Example solution: Use a for loop to append six fruits to an empty list. Sort the list into alphabetical order and print it. Enter a fruit: strawberry Enter a fruit: kiwi Enter a fruit: lemon Enter a fruit: pear Enter a fruit: orange Enter a fruit: mango Sorted fruit: kiwi lemon mango orange pear strawberry Searching Through Lists A simple if statement can be used to see if a certain value appears within a list. names = [ "Alex" , "Bill" , "Charlie" , "Darla" ] name = input ( "Enter a name: " ) if name in names: print ( "Yes," , name , "is in the list." ) else : print ( "Sorry," , name , "is not in the list." ) Enter a name: Bill Yes, Bill is in the list. Enter a name: Sadie Sorry, Sadie is not in the list. Lists Task 12 (Packed Suitcase ) Example solutions: Create a list with five items to take on holiday. Ask the user to input an item and use an if statement to check if it is or isn't in the list. What should I pack? sun cream I've already packed sun cream What should I pack? toothpaste Whoops! I forgot to pack toothpaste Calculating the Sum of a List To calculate the sum of a list of numbers there are two methods. Using Python's built-in sum function : numbers = [1,4,2,3,4,5] print ( sum (numbers)) Both methods will result in the same output : 19 Using a for loop to cycle through each number in the list and add it to a total . numbers = [1,4,2,3,4,5] total = 0 for number in numbers: total = total + number print (total) Lists Task 13 (Sum and Average ) Example solution: Use a for loop to ask the user to input 5 numbers and append each to a list. Use the sum command to output the total and use it calculate the average . Enter a number: 6 Enter a number : 7 Enter a number : 6 Enter a number : 9 Enter a number : 4 The total is 32 The average is 6.4 Extending a List .extend() can be used in a similar way to .append() that adds iterable items to the end of a list . This commands works well with the choice command (imported from the random library ) to create a list of characters that can be randomly selected. The code below adds a lowercase alphabet to an empty list and then, depending on the choice of the user, adds an uppercase alphabet too. The choice command is used in a loop to randomly select 5 characters. Using .extend() to make a random 5-character code from random import choice list = [] list. extend ( "abcdefghijklmnopqrstuvwxyz" ) upper = input ( "Include uppercase letters? " ) if upper == "yes" : list. extend ( "ABCDEFGHIJKLMNOPQRSTUVWXYZ" ) code = "" for number in range (5): letter = choice (list) code = code + letter print ( "Your five character code is" , code) Possible outputs: Include uppercase letters? yes Your five character code is yPfRe Include uppercase letters? yes Your five character code is GJuQw = Include uppercase letters? no Your five character code is gberv Extend treats each character as an indidual item whereas append adds the whole string as a single entity . Most of time append would be used, but extend is suitable for a password program as additional individual characters can be added to a list depending on the parameters (e.g. lowercase letters, uppercase letters, numbers and special characters). list = [] list. extend ( "ABCD" ) list. extend ("EFGH" ) print (list) list = [] list. append ( "ABCD" ) list. append ("EFGH" ) print (list) ['A','B','C','D','E','F','G','H'] ['ABCD' , 'EFGH'] = = Practice Task 14 Use the code above (for a 5-character code ) to help you make a password generator . Ask the user if they want uppercase letters , numbers and special characters and use the extend command to add them to a list of characters if they type yes (you should extend lowercase characters into an empty list regardless, like in the code above). Use a for loop and the choice command (imported from the random library) to randomly generate a 10-character password . Example solutions: Include uppercase letters? yes Include numbers? yes Include special characters? yes Your new password is RjWSbT&gW5 Include uppercase letters? no Include numbers? yes Include special characters? no Your new password is hdf8se9y2w ⬅ Section 7 Practice Tasks 8b - 2D Lists ➡

Learn about the two types of data storage unit systems and how the increments work, including kilobyte and kibibyte. Based on the 2016 OCR Cambridge Technicals Level 3 IT specification. 1.7 - Units of Measurement Exam Board: OCR Specification: 2016 - Unit 1 All computer systems communicate , process and store data using binary because this is the format that the processor understands . Binary is a number system consisting entirely of 0s and 1s . A single binary data value (a 0 or a 1 ) is called a bit . 4 bits is called a nibble (e.g. 0101 or 1100). 8 bits is called a byte (e.g. 10101001 or 01011100). There are two main measurement systems : Metric Units of Measurement The gap between units when using metric values (also known as the decimal system ) is always 1,000 . For example, there are 1,000 bytes in 1 kilobyte and 1,000 kilobytes in 1 megabyte . To convert between metric units , divide by 1,000 when moving to a larger unit (e.g. 500 megabytes is 0.5 gigabytes ) and multiply by 1,000 when moving to a smaller unit (e.g. 4.7 terabytes is 4,700 gigabytes ). For example, 8,520 KB is the same as 8.52 MB or 0.00825 GB . Metric values (usually) have a prefix ending in ‘ a ’ such as mega byte or giga byte. Binary Units of Measurement The gap between units when using binary values is always 1,024 . For example, there are 1,024 bytes in 1 kibibyte and 1,024 kibibytes in 1 mebibyte . To convert between binary units , divide by 1,024 when moving to a larger unit (e.g. 4,096 kibibytes is 4 mebibytes ) and multiply by 1,024 when moving to a smaller unit (e.g. 55 pebibytes is 55,296 tebibytes ). For example, 34 KiB is the same as 34,816 MiB or 35,651,584 GiB . Bi nary values have a prefix ending in ‘ bi ’ , such as ki bi byte or me bi byte. Computer scientists often use the binary system of measurement because the storage size is technically more accurate . Q uesto's Q uestions 1.7 - Units of Measurement: 1 a. Create a table or list that clearly shows the relationship between values from bit up to petabyte for the metric (decimal) measurement system . [4 ] 1 b. Create another table to display the binary measurement system from bit to pebibyte . [4 ] 2. Make the following conversions and show your working out . [2 each ] a. 40 megabytes into kilobytes . b. 8500 gigabytes into terabytes . c. 100 mebibytes into kibibytes . d. 854,016 mebibytes into gibibytes . e. How many bytes are there in 3 megabytes ? f. How many bytes are there in 3 mebibytes ? 1.6 - Hardware Troubleshooting 1.8 & 1.9 - Number Systems Topic List

Learn about HTML, CSS, JavaScript, search engine indexing, the PageRank algorithm and client-side and server-side processing. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 3.4 - Web Technologies Specification: Computer Science H446 Watch on YouTube : HTML CSS JavaScript Search engine indexing PageRank algorithm Server-Side & Client-Side Processing This topic looks at the languages that web pages are comprised of (HTML , CSS and JavaScript ) as well as search engines and network processing (client-side and server-side ). HTML HTML ( HyperText Markup Language ) is the standard language used to create and structure web pages . It uses tags enclosed in angle brackets to define elements on a page . A web page begins with , which contains a section for metadata , links and the

Learn about programming paradigms such as procedural language (e.g. Python), assembly language (including Little Man Computer) and object-oriented programming (OOP) language (e.g. Java). Methods of memory addressing (immediate, direct, indirect and indexed) are also covered. Based on the OCR H446 Computer Science A-Level specification. Exam Board: OCR A-Level 2.4 - Types of Programming Language Specification: Computer Science H446 Watch on YouTube : Programming Paradigms Procedural Language Little Man Computer Addressing Modes Object-Oriented Language Programming paradigms are different approaches to writing and structuring code to solve problems . The procedural paradigm focuses on step-by-step instructions and the use of functions to organise tasks . The assembly paradigm operates at a low level , giving direct control over hardware through processor-specific instructions . The object-oriented paradigm models programs around objects that combine data ( attributes ) and behaviour ( methods ), promoting modular and reusable design . Procedural Language A procedural programming language organises code into reusable blocks ( procedures or functions ), which perform specific tasks in a step-by-step manner . It focuses on a clear sequence of instructions that operate on data, often using variables , loops and conditionals . Examples include Python , C , Pascal and BASIC . These languages are commonly used for software development , data processing and teaching programming fundamentals as they emphasise logical structure and modular design . Assembly Language / Little Man Computer Assembly language is a low-level programming language that uses short , readable codes called mnemonics to represent machine-level instructions executed by the CPU . Each command in assembly corresponds closely to a specific hardware operation , making it highly efficient but difficult to write and maintain . It is mainly used for embedded systems , device drivers and performance-critical tasks where direct control of hardware is required . For the OCR A-Level course , you must understand and be able to write code using the 11 mnemonics of Little Man Computer ( LMC ), which is an educational form of assembly language . Modes of Addressing Memory An addressing mode in assembly language defines how the CPU should locate the data (operand ) needed for an instruction (opcode ). It tells the processor whether the data is stored directly in the instruction , in memory , or needs to be calculated using an address or register . There are four main types : Immediate addressing : The operand contains the actual data to be used , rather than a memory address. Direct addressing : The operand contains the memory address where the required data is stored . Indirect addressing : The operand contains an address that points to another memory location holding the actual data . Indexed addressing : The operand provides a base address that is adjusted by the value in an index register to find the final memory address of the data . Object-Oriented Language An object-oriented programming ( OOP ) language organises code around objects , which combine data ( attributes ) and behaviour ( methods ) into reusable units . Key features of OOP : Classes are templates from which objects are created . Classes define both attributes (data ) and methods (functions or behaviours ). Encapsulation allows data to be protected by making attributes private and providing controlled access through public methods . Inheritance enables a class to reuse or extend the attributes and methods of a parent class , promoting the reuse of code . Polymorphism allows methods or attributes to behave differently depending on the object or class that uses them . Examples of OOP languages include Java , Python , C++ and C# . These languages are widely used for large-scale software development , game development and graphical user interfaces , where modularity and code reuse are crucial . Programming Paradigms Q uesto's K ey T erms Programming Paradigms: procedural language, assembly language, object-oriented language Procedural Language: input, output, comments, variables, casting, count-controlled iteration, condition-controlled iteration, logical operators, selection, string handling, subroutines, arrays, files Assembly Language: Little Man Computer, INP, OUT, LDA, STA, ADD, SUB, HLT, DAT, BRA, BRP, BRZ Modes of Addressing Memory: immediate, direct, indirect, indexed, index register, opcode, operand Object-Oriented Language: class, method, attribute, encapsulation, inheritance, polymorphism, instantiation, constructor method, get method, set method D id Y ou K now? Python was named after the 1970s British comedy group ' Monty Python ', not the snake . Guido van Rossum created Python in the late 1980s during his Christmas holidays as a ' hobby project '. 2.3 - Software Development A-Level Topics 3.1 - Compression & Encryption

Learn how to create print statements in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. top Python 1a - Printing Printing in Python To output a message onto the screen, use the print command. Then place your message within brackets and speech marks . For example: print ( "Welcome to Python!" ) When you run the program, the text will print to the Python console: Welcome to Python! Printing Task 1 (Full Name & To Your Left) On the first line, print your first name and surname. On the next line, write another print statement to print t he name of the person (or thing) to your left. Example solution: Elsie Parker pencil case Printing over Several Lines One way of writing across multiple lines is to write several print commands like this: print ( "Welcome to...." ) print ( "Computer Science " ) print ( "Newbies!!! " ) = Welcome to .... Computer Science Newbies!!! However, when we program, we always want to make our code the most efficient it can be by using as few lines as possible . Therefore you can write \n within a printed statement to move it to the next line. Make sure you use \ and not / otherwise it will print the slash and not make a new line! print ( "Welcome to....\n Computer Science\n Newbies!!! " ) = Welcome to .... Computer Science Newbies!!! Both pieces of code display the same thing, but the second one is more efficient because it only uses one line. Printing Task 2 (Name, Colour, Movie) Use \n to write your name, favourite colour and favourite movie in only one line of code. Example solution: Matthew yellow Interstellar ⬅ Setting Up Python 1b - Comments ➡

Learn about the six programming errors - syntax, runtime (execution), linking, logical, rounding and truncation. Based on the 2020 Eduqas (WJEC) GCSE specification. 10.3: Programming Errors Exam Board: Eduqas Specification: 2020 Syntax Error A syntax error is a mistake in the grammar or spelling of the program. A syntax error will prevent the program from being compiled . Examples: Incorrect Spelling: pront ( "hello" ) Incorrect punctuation: print ( "hello" ( Execution (Runtime) Error An execution error is when the program unexpectedly stops as a result of an operation during execution . Examples: Dividing by zero: 400 / 0 Reading too far in a file: #There are 50 lines in the file line = file.readlines( ) print ( line [100] ) Logical Error Linking Error A logical error is a mistake made by the programmer - the program still works but displays the wrong output . Examples: Truncation Error Rounding Error A linking error occurs when a compiler can’t find a sub procedure (e.g. the random library in Python) that has been used. The programmer might have declared it incorrectly or forgotten to link (import) it . Examples: Spelling an import command incorrectly: import ramdon number = random.randint(1,10) Requesting a function without linking: number = random.randint(1,10) Incorrect calculation: total = num1 - num2 print (total) Incorrect variable printed: age = 16 name = "Steve" print ( "Nice to meet you" , age) A rounding error is when the program rounds a real number to a fixed number of decimal places. This results in losing some value as the number becomes less accurate . Examples: Rounding up: 80.87 = 80.9 (Inaccurate by 0.03) Rounding down: 63.4 = 63 (Inaccurate by 0.4) A truncation error is when the program truncates a real number to a fixed number of decimal places . This results in losing some value as the number becomes less accurate . Examples: Truncation to 2 decimal places: 92.13787 = 92.13 (Inaccurate by 0.00787) Truncation to 1 decimal place: 25.199876 = 25.1 (Inaccurate by 0.099876) Q uesto's Q uestions 10.3 - Programming Errors: 1. Describe and give an example of each type of error: a. Syntax Error [ 3 ] b. Execution (Runtime) Error [ 3 ] c. Logical Error [ 3 ] d. Linking Error [ 3 ] e. Rounding Error [ 3 ] f. Truncation Error [ 3 ] 2. State the error that will occur for each scenario: [1 each ] a. A command word (such as for or print) has been misspelt. b. The average speed is 120.3856 but only 120.3 is displayed. c. The cost of a meal is £47 but £40 is displayed. d. A program uses a subroutine that has not been imported. e. The height of a dog is 33.38cm but 33.4cm is displayed. f. The user wants to read line 9 of a file that only has 6 lines. g. The user's age is printed instead of their name. h. The programmer has typed print("hello"( i. A number is divided by 0. j. The program is asked to generate a random number but 'import random' has not be written. 10.2 - Stages of Compilation Theory Topics 11.1 - Impacts of Technology

Navigate between all Unit F161 (Developing Application Software) topics in the OCR Cambridge Advanced National in Computing (AAQ) specification. Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F161: Developing Application Software Certificate: Computing: Application Development (H029 / H129) Unit F161: Developing Application Software These pages are based on content from the OCR Cambridge Advanced National in Computing (AAQ) specification . Unit F161 YouTube Playlist Topic 1: Application Software Considerations 1.1 - Application Platforms 1.2 - Devices 1.3 - Storage Locations Topic 2: Data & Flow in Application Software 2.1 - Data Formats & Types 2.2 - Data Flow 2.3 - Data States Topic 3: API & Protocols 3.1 - Application Programming Interfaces (API) 3.2 - Protocols Topic 4: Application Software Security 4.1 - Security Considerations Topic 5: Operational Considerations 5.1 - Testing 5.2 - Types of Application Software Installation 5.3 - Policies Topic 6: Legal Considerations 6.1 - Legal Considerations

A complete list of tags required for students to know how to use in the 2016 Eduqas GCSE specification. Follow the links on each tag to see how to use them. Here you can find a list of tags. Click a tag to see how to use it. Tags for Eduqas GCSE:

Learn about the three elements of computational thinking - abstraction, decomposition and algorithmic thinking. Based on the J277 OCR GCSE Computer Science specification (first taught from 2020 onwards). 1.1: Computational Thinking Exam Board: OCR Specification: J277 There are three key components to computational thinking (smart problem solving): Abstraction is when you ignore unnecessary information and focus only on the important facts . Abstraction is used because it simplifies a problem to make it less complex . This makes it more straightforward to understand the problem and create a solution . Decomposition is when you break a problem down into smaller tasks so that it is easier to solve . Each individual problem can be separately tested and solved . Decomposition also enables different people to work on the different parts of a larger problem that can later be recombined to produce a full solution . Algorithmic thinking is the final stage as logical steps are followed to solve the problem . The problem is broken down using decomposition into smaller problems . The required data and relevant data structures are considered using abstraction . Watch on YouTube : Abstraction Decomposition Algorithmic Thinking Q uesto's Q uestions 1.1 - Computational Thinking: 1. What does the term 'abstraction ' mean? Why is it important ? [2 ] 2. What is meant by ' decomposition '? Why is it important ? [ 2 ] 3. What is algorithmic thinking ? What does it involve? [3 ] Theory Topics 1.2 - Designing Algorithms

Learn how to split, edit and removes lines using files in Python. Try practice tasks and learn through text and images. Perfect for students learning GCSE Computer Science in UK schools. Python 10c - REMOVE & Edit LINES Splitting a File The split command is used to split up a line of a file into different parts . The character or string in brackets after the split command is the value that will denote each split . In the example below I have split the file at each comma . Remember that Python numbering starts at 0 so the first section is 0, not 1. 0 1 2 3 The program below splits each line of the file at each forward-slash ( / ). The printed statement is the employee's first name, surname and job position. 0 1 2 3 4 Practice Task 1 Create a file (new txt document in Notepad) called movies. Type in the movie name, main actor, genre (e.g. horror), year it was released and your rating out of 10. Print just the movie name and year it released. Example solution: Deleting Lines in a File Exact Line Name The code below shows how to remove a line from a file using the exact name of the line , which will only work for short or simple files . First open the file in read move to save each line in a variable I've named lines. Then ask the user to input the exact line they want to remove (e.g. 'plum' in my example). Then open the file in write mode and use a for loop to read each line and only write it back into the file if it isn't equal to the line the user entered - such as 'plum'. The line.rstrip() command is important as it removes any spaces or empty lines that may interfere with matching the line to the input. Deleting Lines in a File Word in the Line The code below shows how to remove a line from a file if a certain word appears in that line , although this could be dangerous with large files. In my example I have written apple which has also removed pineapple! The difference from the previous program is to change the for loop so that it checks if the inputted word appears in the line . If it does appear then nothing happens (except a print statement to acknowledge it's been found). If the word doesn't appear then that line can be safely rewritten to the file . Practice Task 2 Download the trees text file. Give the user a choice of removing a specific tree or a type of tree. If they choose a specific tree then remove the line if it is an exact match (e.g. Field Maple). If they choose to remove a type of tree remove all lines that contain the name of that tree (e.g. willow) Make sure you actually check the file to see if the lines have been removed correctly! Example solution: Download the trees file: Sorting a File Sorting a file into alphabetical (or numerical ) order is a simple process. Open the file in read mode and save the lines into a list . The sort c ommand will automatically order the list of lines. If necessary, in the brackets type reverse = True to sort the list in reverse. Practice Task 3 Expand on your tree program from the previous practice task. As well as SPECIFIC or TYPE, allow the user to enter SORT to sort the tree file either in alphabetical order or reverse alphabetical order. Check the text file to see if it has been sorted correctly. You may make this a separate program from task 2 if you wish. Example solution: Editing Lines in a File Overwriting data in a file is a tricky process. The program below uses the same Employees.txt file as above but allows the user to change the address of an employee . A temporary file is created to store the lines of the employee file, but the line with the changes is replaced specifically with the new address. I have explained each line of the program to the right: When I executed the program below I entered Thomas Wynne's details and changed his address. When I opened the employees file the address had been updated : 1: Importing os allows me to rename and remove files later in the program. 3: Opens the employee file in read mode . 5 - 8: Input lines allow the user to enter the first name, surname and the person's new address. 10: A found flag is set up and set to False . 12: The for loop cycles through each line in the file. 13: Each line is split into separate parts from each / . 15: An if statement checks if the first name and surname match an employee in the file. 16: A replacement line is created by putting the original line together but with the new address. 18: The found flag is changed to True because the employee first name and surname matched . 19: A temporary file is created and opened in write mode . 20: The seek command restarts the file at line 0 . 22: The for loop cycles through each line of the employee file from the beginning. If the first name and surname match it will write the new line to the file, otherwise it will rewrite the original line . 28 & 29: Both files are closed . 31 & 32: If the names didn't match , an appropriate message is printed. 34 - 37: If the address was changed, the original file is renamed and deleted and the temp file is renamed as the original file. Practice Task 4 Use the movie file you created for practice task 1. Ask the user to enter the name of a movie. Ask them to enter an updated rating out of 10. Update the file to change the rating to the new value. Example solution: ⬅ 10b - Read & Search Files Section 10 Practice Tasks ➡

Learn about the purpose, characteristics, advantages, disadvantages, examples and client requirements of application software categories including open, closed, shareware, freeware and embedded software. Resources based on Unit F160 (Fundamentals of Application Development) for the OCR Cambridge Advanced National in Computing (H029 / H129) AAQ (Alternative Academic Qualification). Qualification: Cambridge Advanced National in Computing (AAQ) Unit: F160: Fundamentals of Application Development Certificate: Computing: Application Development (H029 / H129) 1.3.2 - Application Software Categories Watch on YouTube : Open Software Closed Software Shareware Freeware Embedded Software There are five application software categories you need to know : Open Closed Shareware Freeware Embedded For each software category you need to know : Its purpose and common characteristics . The types of devices the software may be used on. The advantages and disadvantages of using the software. How client requirements affect the selection of that software. Application Categories Open Software Closed Software Open (usually known as open-source ) software is developed to be freely accessible and allow users to view , modify and distribute the source code . Its purpose is to promote collaboration and customisation when developing software . Closed (or closed-source or proprietary ) software is developed and distributed by a company or individual who owns the source code . The purpose is to maintain control , generate profit and ensure a consistent user experience . Shareware Shareware is closed software that is distributed for free on a trial basis , often with limited features or time restrictions . The purpose is to let users try before they buy , encouraging them to later purchase the full version . Freeware Freeware is closed software that is completely free to use , usually without restrictions like time limits or limited features , but still owned by a developer or company . The purpose is to provide software for free while retaining control over its code and distribution . Embedded Software Embedded software is designed to run on specific hardware and perform dedicated tasks . It is usually built into devices that are not traditional computers (like washing machines or microwaves ), allowing those devices to function efficiently and potentially automatically . Q uesto's Q uestions 1.3.2 - Application Software Categories: 1. Summarise the five categories of application software in two sentences each . [5 ] 2. An independent video game company has made a short game with just three levels. Justify which application software category they should use and why . [4 ] 3. Describe the advantages and disadvantages of using embedded software . [ 4 ] WinRAR is a shareware compression tool with a 40-day free trial , but it never actually locks users out. Since 1995 , WinRAR has been downloaded an estimated 500 million times . D id Y ou K now? 1.3.1 - Application Types Topic List 1.3.3 - Application Software Types