Glasgow | 26-ITP-May | Chan Yat Long | Sprint 1 | Coursework

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

@@ -1,3 +1,4 @@
+
 let count = 0;
 
 count = count + 1;

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

@@ -5,7 +5,15 @@ 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 = ``;
+
+function first(firstName, middleName, lastName){
+
+    let initials = firstName.slice(0,1) + middleName.slice(0,1) + lastName.slice(0,1);
+
+  return `${initials}`;
+}
+console.log(first(firstName, middleName, lastName));
+
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -11,13 +11,15 @@
 
 const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
 const lastSlashIndex = filePath.lastIndexOf("/");
+
+// 1. Get the base (file.txt)
 const base = filePath.slice(lastSlashIndex + 1);
 console.log(`The base part of ${filePath} is ${base}`);
 
+const dir =  filePath.slice(0, lastSlashIndex);
+
 // 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 = ;
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -3,7 +3,18 @@ const maximum = 100;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
+Math.floor is a function to make sure it is a whole number.
+
+The fuction will randomly choose a decimal number from 0 - 1. 
+After that will do the Math(100-1+1) and multiply the decimal value and add 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
+
+
+

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? 
+

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;
-age = age + 1;
+function X(num){
+const age = num +1; 
+return age;}
+console.log(X(33));

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 ?
-
-console.log(`I was born in ${cityOfBirth}`);
-const cityOfBirth = "Bolton";
+const cityOfBirth = "BOlton";
+const sentence = `I was born in ${cityOfBirth}`;
+console.log(sentence);

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

@@ -1,5 +1,13 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const last4Digits = cardNumber.toString().slice(-4);
+console.log(last4Digits);
+
+because it doesn't have console.log, so it doesn't print the result. 
+but it gives the function errors.
+
+it is not what I expected, because we should change the number into string, because it is not a
+function.
+
 
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working

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

@@ -1,2 +1,6 @@
-const 12HourClockTime = "8:53pm";
-const 24hourClockTime = "20:53";
+const twelvehourClockTime = "8:53pm";
+const twentyfourhourClockTime = "20:53";
+
+console.log(twelvehourClockTime);
+console.log(twentyfourhourClockTime);
+

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 +12,33 @@ 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 4 function calls here. There are two when you use Number();
+ The other call is about console.log() to print the string out.
+ When you call the variable (priceDifference/ carPrice), it is a function call. 
+The last one is
 
 // 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?
 
+It shows that I miss a ) parenthesis.
+
+
 // c) Identify all the lines that are variable reassignment statements
 
+carPrice = Number(carPrice.replaceAll(",", ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+
 // d) Identify all the lines that are variable declarations
 
-// e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+let carPrice = "10,000";
+let priceAfterOneYear = "8,543";
+
+const priceDifference = carPrice - priceAfterOneYear;
+const percentageChange = (priceDifference / carPrice) * 100;
+
+// e) Describe what is the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+It deletes all the comma insides.I
+The Number helps convert that string into an actual figure.
+
+
+

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

@@ -12,14 +12,31 @@ 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?
+ Six, the const with the functions inside.
+
 
 // b) How many function calls are there?
+4
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
 
+It is called the remaining function, because if you use this function , you will use the remainingMinutes to divides 60 and get the remaining value .
+
+
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+It calls the variable movieLength and remainingSeconds and substract together and divide it 60.
+
+
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+I think it represents the total hour , remaining minutes and the remaining seconds .Duration is a better name
+
+
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+yes
+I tried to put 6(second), 60(1 minute), 3600(equivalent to 1 hour)
+
+
+

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

@@ -24,4 +24,17 @@ console.log(`£${pounds}.${pence}`);
 // Try and describe the purpose / rationale behind each step
 
 // To begin, we can start with
-// 1. const penceString = "399p": initialises a string variable with the value "399p"
+
+line 1. const penceString = "399p": initialises a string variable with the value "399p"
+line 3. You define a penceStringWithoutTrailingP variable and call a function to cut a line, you use penceString.length -1 because 
+you want to cut the p. 
+
+line 8: You define a variable paddedPenceNumberString and call a function to add 0 into the letters, if the words are not three characters long.
+line 9: You want to take the pound out of 399, so you call the function substring and only wants before the index 1, which is calculated by (0 , length -2); 
+
+line 14: You call a variable function and you subtract the value from index 1 to the end. 
+line 18: print the variable pound and the variable pence with the . 
+
+
+
+

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

@@ -1,13 +1,25 @@
-// Predict and explain first...
-//  =============> write your prediction here
 
-// call the function capitalise with a string input
-// interpret the error message and figure out why an error is occurring
 
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  let str = '${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
 }
 
-// =============> write your explanation here
-// =============> write your new code here
+It said syntaxError because identifier 'str' has already been declared 
+because we should use backtick`` to wrap the template literal.The first one of the bracket is a
+single quote, not a backtick.
+
+  Also, since str has already been declared as a parameter, we should not use it to define as variable.
+
+
+
+
+
+function capitalise(str) {
+
+  let result = `${str[0].toUpperCase() + str.slice(1)}`;
+  return result;
+}
+
+console.log(capitalise("str"));
+

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

@@ -1,10 +1,3 @@
-// Predict and explain first...
-
-// Why will an error occur when this program runs?
-// =============> write your prediction here
-
-// Try playing computer with the example to work out what is going on
-
 function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
@@ -14,7 +7,19 @@ function convertToPercentage(decimalNumber) {
 
 console.log(decimalNumber);
 
-// =============> write your explanation here
+The terminal shows the syntax error because decimal number has been declared.
+because the decimal number is a variable which is not supposed to define in the function, 
+but the decimal number has been defined insides the functon, so it will forever return 50 %.
+  Also, when we call the fucnton, we should name the function convertToPercentage.
+
+
+
+function convertToPercentage(decimalNumber) {
+
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(convertToPercentage(0.5));
 
-// Finally, correct the code to fix the problem
-// =============> write your new code here

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

@@ -1,20 +1,22 @@
 
-// Predict and explain first BEFORE you run any code...
 
-// this function should square any number but instead we're going to get an error
-
-// =============> write your prediction of the error here
 
 function square(3) {
     return num * num;
 }
 
-// =============> write the error message here
 
-// =============> explain this error message here
+    It shows the syntax error which is an unexpected number;
+    because we should not put 3 insides the variable, because it will lead to variable: num not defined
+insides the function, so the 3 doesn't work insides the function.
+
+We need to put num instead of 3 insides the();
+That way when we call the function by using console.log.The 3 will go into the num variable.
+
 
-// Finally, correct the code to fix the problem
+function square(num) {
+    return num * num;
+}
 
-// =============> write your new code here
 
 

Sprint-2/2-mandatory-debug/0.js

@@ -1,14 +1,20 @@
-// Predict and explain first...
 
-// =============> write your prediction here
+The problem is unexpected identifier "problem"
+The problem is the result doesn't print the mulitplication of the number,
+because we should not call the function inside the function;
+
 
 function multiply(a, b) {
   console.log(a * b);
 }
 
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
-// =============> write your explanation here
+Instead, we should define the expression a * b
+and return the expression.
+
+/ function multiply(a, b) {
+    return (a * b);
+  }
 
-// Finally, correct the code to fix the problem
-//  =============> write your new code here
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);

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

@@ -1,5 +1,5 @@
-// Predict and explain first...
-//  =============> write your prediction here
+Unexpected identifier "problem"
+variable hasn't been defined so the variable cannot do function.
 
 function sum(a, b) {
   return;
@@ -8,6 +8,14 @@ function sum(a, b) {
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
-// =============> write your explanation here
-// Finally, correct the code to fix the problem
-//  =============> write your new code here
+
+because return should be followed by a + b;
+the final result doesn't return the value. 
+
+
+function sum(a, b) {
+  return;
+  a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);