Cape Town | 26-ITP-May | Shafiek Walker | Sprint 1 | Coursework Exercises

Sprint-1/1-key-exercises/1-count.js

@@ -3,4 +3,4 @@ let count = 0;
 count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
-// Describe what line 3 is doing, in particular focus on what = is doing
+// Line 3 adds 1 to the current value of count and assigns the result back to count using the = operator.

Sprint-1/1-key-exercises/2-initials.js

@@ -4,8 +4,10 @@ let lastName = "Johnson";
 
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
+// [0] accesses the first character of each string and combines them to create the initials.
+// Using template literals (backticks) allows us to easily concatenate the characters together into a single string.
 
-let initials = ``;
+let initials = `${firstName[0]}${middleName[0]}${lastName[0]}`;
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

Sprint-1/1-key-exercises/3-paths.js

@@ -17,7 +17,7 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+const ext = base.slice(base.lastIndexOf(".") + 1);
 
 // https://www.google.com/search?q=slice+mdn

Sprint-1/1-key-exercises/4-random.js

@@ -4,6 +4,14 @@ const maximum = 100;
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
 // In this exercise, you will need to work out what num represents?
+//num becomes A random whole number between 1 and 100.
+
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+// Math.random() creates a random decimal number.
+// The number will always be between 0 and 1, but it will never actually reach 1.
+
+// Math.floor() rounds down the decimal number that is created after
+// Math.random() is multiplied by the range.

Sprint-1/2-mandatory-errors/0.js

@@ -1,2 +1,2 @@
-This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
+// This is just an instruction for the first activity - but it is just for human consumption
+// We don't want the computer to run these 2 lines - how can we solve this problem?

Sprint-1/2-mandatory-errors/1.js

@@ -1,4 +1,5 @@
 // trying to create an age variable and then reassign the value by 1
+// A const variable cannot be reassigned.It it constant
 
-const age = 33;
+let age = 33;
 age = age + 1;

Sprint-1/2-mandatory-errors/2.js

@@ -1,5 +1,5 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
-// what's the error ?
+// what's the error ? - The variable is being used before it's declared
 
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

Sprint-1/2-mandatory-errors/3.js

@@ -1,9 +1,19 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+// I fixed the error by replacing the original expression instead of declaring
+// last4Digits a second time. Declaring a const twice causes a SyntaxError.
+const last4Digits = cardNumber % 10000;
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
+
 // Before running the code, make and explain a prediction about why the code won't work
+// .Slice only works on strings, not numbers. Therefore, the code will throw an error 
+
 // Then run the code and see what error it gives.
+// Uncaught TypeError: cardNumber.slice is not a function
+
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
+// The error is what I predicted. The slice method is not a function that can be used on numbers, only strings.
+
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+

Sprint-1/2-mandatory-errors/4.js

@@ -1,2 +1,4 @@
-const 12HourClockTime = "8:53pm";
-const 24hourClockTime = "20:53";
+const twelveHourClockTime = "8:53pm";
+const twentyFourHourClockTime = "20:53";
+
+// Variable names cannot start with a number, so the variable name "24HourClockTime" and "12HourClockTime" is invalid.

Sprint-1/3-mandatory-interpret/1-percentage-change.js

@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -12,11 +12,22 @@ console.log(`The percentage change is ${percentageChange}`);
 // Read the code and then answer the questions below
 
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
+// There are 5 function calls in this file.
+// Line 4 calls replaceAll() and Number().
+// Line 5 calls replaceAll() and Number().
+// Line 10 calls console.log().
 
 // b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
+// The error was on line 5.
+// After using replaceAll(), priceAfterOneYear was still a string instead of a number.
+// I fixed it by wrapping the result in Number(), so it was converted to a number before doing the calculation.
 
 // c) Identify all the lines that are variable reassignment statements
+// Lines 4 and 5 are variable reassignment statements because its declared on lines 1 and 2.
+
 
 // d) Identify all the lines that are variable declarations
+// Lines 1, 2, 7, and 8 are variable declarations because they declare variables using let and const.
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//// Removes commas and converts the string to a number.

Sprint-1/3-mandatory-interpret/2-time-format.js

@@ -1,4 +1,4 @@
-const movieLength = 8784; // length of movie in seconds
+const movieLength = 3665; // length of movie in seconds
 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
@@ -12,14 +12,30 @@ console.log(result);
 // For the piece of code above, read the code and then answer the following questions
 
 // a) How many variable declarations are there in this program?
+/* 6 -  movieLength
+remainingSeconds
+totalMinutes
+remainingMinutes
+totalHours
+result */
 
 // b) How many function calls are there?
+// 1, console.log() is the only function call in this program
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// % returns the remainder.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// The expression assigned to totalMinutes is calculating the total number of minutes in the movie length 
+// by subtracting the remaining seconds from the total movie length and then dividing that value by 60.
+// This gives us the total number of whole minutes in the movie length.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// The variable result stores the movie duration as a formatted string (hours:minutes:seconds).
+// A better name would be "formattedMovieLength".
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// The code works when movieLength is 3665. It outputs "1:1:5", which is correct,
+// but the formatting is not ideal. A better formatted output would be "1:01:05".
+// The code works for whole numbers, but it does not pad single-digit minutes and seconds with leading zeros.

Sprint-1/3-mandatory-interpret/3-to-pounds.js

@@ -25,3 +25,9 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 2. Removes the trailing "p" from the string.
+// 3. Adds leading zeros if needed.
+// 4. Extracts the pounds value.
+// 5. Extracts the pence value.
+// 6. Logs the formatted price (£3.99).
+// Final output: "£3.99".

Sprint-1/4-stretch-explore/chrome.md

@@ -11,8 +11,12 @@ In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
 What effect does calling the `alert` function have?
+It displays a pop-up message with the text "Hello world!" and waits for the user to close it.
 
 Now try invoking the function `prompt` with a string input of `"What is your name?"` - store the return value of your call to `prompt` in an variable called `myName`.
 
 What effect does calling the `prompt` function have?
+It displays a dialog box asking the user for input.
+
 What is the return value of `prompt`?
+It returns the text the user entered as a string.

Sprint-1/4-stretch-explore/objects.md

@@ -5,12 +5,16 @@ In this activity, we'll explore some additional concepts that you'll encounter i
 Open the Chrome devtools Console, type in `console.log` and then hit enter
 
 What output do you get?
+ƒ log() { [native code] }
 
 Now enter just `console` in the Console, what output do you get back?
-
+console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
 Try also entering `typeof console`
-
+" object"
 Answer the following questions:
 
 What does `console` store?
+console is an object that stores functions used for debugging and displaying messages.
+
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+The . accesses a property or method on an object.