London | ITP-Jan 26 | Maryanne Mosonik | Sprint 1 | Coursework

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

@@ -4,3 +4,4 @@ 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 is updating the value of count by adding 1 to its current value. The = operator is an assignment operator, which assigns the result of the expression on the right (count + 1) to the variable on the left (count). So, after line 3 is executed, count will have a new value that is one greater than its previous value.

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

@@ -5,7 +5,7 @@ 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.
 
-let initials = ``;
+let initials = firstName.charAt(0)+ middleName.charAt(0) + lastName.charAt(0);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -17,7 +17,8 @@ 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 = filePath.slice(filePath.lastIndexOf(".") + 1);
+
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -7,3 +7,6 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // 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() returns a random number between 0 and 1 but not including 1. By multiplying by (maximum-minimum +1) we get a random number between 0 and 100. 
+// The answer could however be in decimal point, thereofor by using Math.floor() we round down to the nearest whole number, but that would give us a range between 0 and 99. Adding minimum (1) to the result gives us a range between 1 and 100 inclusive.

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? - I have added a slash to make it a comment. 

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

@@ -1,4 +1,5 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+// use let instead of const to declare the age variable, as const variables cannot be reassigned.

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

@@ -1,5 +1,6 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
-
-console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);
+
+//you have to define the variable first before you can use it. 

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

@@ -1,9 +1,11 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const last4Digits = cardNumber.toString().slice(-4);
 
 // 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
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+// The error is because the slice method is being called on a number, but slice is a string method. To fix this, we can convert the cardNumber to a string before calling slice. I have fixed it by using the toString() method. 

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

@@ -1,2 +1,2 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const twentyFourHourClockTime = "20:53";
+const twelveHourClockTime = "08:53";

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;
@@ -11,12 +11,14 @@ 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
+// 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. On line 4,5 and 10. 
 
 // 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?
-
+//Syntax error on line 5 which has been fixed. 
 // c) Identify all the lines that are variable reassignment statements
-
+// Lines 4 and 5. 
 // d) Identify all the lines that are variable declarations
-
+//Lines 1,2, 7 and 8. 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//It has converted the string "10,000" to a number by first removing the comma using replaceAll() method and then converting the resulting string to a number using the Number() function. This allows us to perform mathematical operations on the carPrice variable.

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

@@ -12,14 +12,20 @@ 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 variable declarations. 
 
 // b) How many function calls are there?
+//1 function call, on line 10. 
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+//The remainder operator returns the remainder left over when movieLength is divided by 60. 
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// The expression (movieLength - remainingSeconds) / 60 calculates the total number of whole minutes in the movie length. It first subtracts the remaining seconds from the total movie length to get a value that is a multiple of 60, and then divides that value by 60 to convert it from seconds to minutes. It gives it as a whole number and is easier to work with. 
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// It represents the movie duration in the format of hours:minutes:seconds. A better name for this variable could be movieDuration. 
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// It does not work for negative values. The code assumes that movieLength is a positive integer representing the length of a movie in seconds. If movieLength is negative, the calculations for remainingSeconds, totalMinutes, remainingMinutes, and totalHours will not produce meaningful results, and the final result will not represent a valid time format. 

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

@@ -25,3 +25,8 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+//2. const penceStringWithoutTrailingP = penceString.substring(0, penceString.length - 1): removes the trailing "p" from the penceString to get just the numeric part of the price in pence.
+//3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"): Ensures that the string always has 3 numbers by adding zeroes to the string if less than 3 characters. 
+//4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2): Extracts the pounds part of the string. The last two digits are pence but the first is pounds. 
+//5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"): Extracts the pence part of the string and ensures its always two digits by adding zeroes when needed. 
+//6. console.log(`£${pounds}.${pence}`): Outputs the final price in pounds and pence format.

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

@@ -11,8 +11,10 @@ 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 the input string. 
 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 the question and asks for your input. 
 What is the return value of `prompt`?
+The name the user enters. 

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

@@ -5,12 +5,18 @@ 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?
+I get this: ƒ log() { [native code] }
 
 Now enter just `console` in the Console, what output do you get back?
+I get this: console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
 
 Try also entering `typeof console`
+I get : object
 
 Answer the following questions:
 
 What does `console` store?
+Console is an object that lets you print messages, errors, warnings etc
+
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+console.log allows you to print messages while assert checks a condition.