London | 25-ITP-Sep | KME Blair | Sprint 1 | Coursework

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

@@ -4,3 +4,5 @@ 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
+// The = operator is used to assign the new count variable as the original count + 1.
+// testing commit 

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.slice(0, 1)+middleName.slice(0, 1)+lastName.slice(0, 1);
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -16,8 +16,11 @@ 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 = filePath.slice(0, lastSlashIndex);
+const ext = base.slice(base.lastIndexOf("."));
+
+console.log(`The dir part of ${filePath} is ${dir}`)
+console.log(`The ext part of ${filePath} is ${ext}`)
 
-const dir = ;
-const ext = ;
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -1,9 +1,21 @@
-const minimum = 1;
+// A program to generate a random number between 1 and 100
 const maximum = 100;
 
-const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
+const num = Math.floor(Math.random() * (maximum)) + 1;
 
 // In this exercise, you will need to work out what num represents?
 // 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
+
+console.log(num);
+
+//Math.random generates a decimal number between 0 and 1
+//multiplying (maximum - minimum + 1) this part generates a number between 0 and 100 that can still have decimal places.
+/// but since minimum in this example is 1 it can be simplified from (maximum -1 +1) ==>(maximum)
+//Math.floor rounds down to the nearest whole number 
+//+ minimum shifts the range from 0-99 to 1-100
+//so the final output is a whole number between 1 and 100, this could also be simplified to +1
+//obviously the function was more useful for different ranges when using the minimum expression
+/// without my simplification, but it is more concise for this specific example.
+

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

@@ -1,2 +1,3 @@
-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?
+//ADD A COMMENT SYMBOL AT THE START OF EACH LINE (WHICH IS // IN JAVASCRIPT)

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;
+//age is a constant variable so cannot be reassigned, can use let instead of const to fix this error

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

@@ -1,5 +1,7 @@
 // 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}`);
+
+//ReferenceError: Cannot access 'cityOfBirth' before initialization
+//  because line 5 should be in front of line 4

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

@@ -1,9 +1,14 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const last4Digits = String(cardNumber).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
+
+// i think the error will be that the slice method works for strings not numbers
+//this code gives TypeError: cardNumber.slice is not a function, this is probably because of the issue i predicted
+//but I don't know for sure base on the error code
+//i will change the cardnumber into a string using String() in the last4Digits expression

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

@@ -1,2 +1,5 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const twelveHourClockTime = "20:53";
+const twentyfourhourClockTime = "08:53";
+
+// there is an error because the expression 12HourClockTime is not a correct syntax,
+// variable names cannot start with a number like that, i will change 12 => twelve 24 => twenty four

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 +12,17 @@ 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
+// lines 4,5 replaceAll() function is called , and then Number() function is called, and then console.log once on line 10
+// so total 5 function calls
 
 // 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?
+// error is in line 5, because of a missing , in replaceAll("," ""), which I will add to fix the problem.
 
 // c) Identify all the lines that are variable reassignment statements
+//lines 4 and 5 are variable reassignment statements
 
 // d) Identify all the lines that are variable declarations
+//lines 1 and 2, as well as 7 and 8 are variable declarations
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//.replaceAll() is removing the , in carPrice and Number() is turning it from a string into 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 = "0"; // length of movie in seconds
 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
@@ -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
 
 // b) How many function calls are there?
+//only 1 function call: console.log()
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+//it gives you the remainder when movieLength is divided by 60
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+//it means it will take the movieLength in seconds, subtract remainingSeconds, and divide the answer by 60 to give the totalMinutes
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+//it is the length of time the movie has been running, remainingLength would be a better name
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+//tried really big, small, and multiples of 60 and found no issue

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

@@ -25,3 +25,13 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 3-6. initializes a constant string variable penceStringWithoutTrailingP which is penceString with the p removed from the end of the string
+//  to give a plain number string
+// 8. initializes a constant string variable paddedPenceNumberString, which pads "0"s at the start
+// of penceStringWithoutTrailingP until it has length=3  the next parts don't delete any numbers accidentally
+// 9-12. initializes a constant string variable pounds, which is the paddedPenceNumberString, with the last two digits
+// subtracted(i.e. the pence value in the string)
+// 14-16. initializes a constant string variable pence, which is the last two digits of paddedPenceNumberString,
+// with "0" pads at the front of the string until it has length=2
+// 18.calls the console.log function to display the pound-sign and then penceString converted into a pound-value
+//