Sheffield | 26-ITP-January | Martha Ogunbiyi | Sprint 2 | Coursework

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

@@ -1,13 +1,26 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// The function when called was supposed to capitalise the first letter of a string by calling the first character of the string and then transforming
+// to uppercase character and adding it back to the string, but because the variable "str" had already been declared it going to throw a syntaxerror
 
 // 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)}`;
-  return str;
-}
-
+// function capitalise(str) {
+//   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+//   return str;
+// }
+// console.log(capitalise("what is your name?"))
 // =============> write your explanation here
+//  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+//       ^
+
+// SyntaxError: Identifier 'str' has already been declared
+// As predicted,when the function is called, it does not compile and throws a syntax error because the identifier "str" had already been declared as a parameter of the function. This violate the rules of JavaScript
+// Variable can be re-assigned using the "let" keyword but cannot be redeclared
 // =============> write your new code here
+function capitalise(str) {
+  let capitalisedStr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalisedStr;
+}
+console.log(capitalise("tell me about yourself"));

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

@@ -2,19 +2,27 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+//The program will return undefined because the console log which is outside the function is calling a local variable within the function scope
 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
-  const decimalNumber = 0.5;
-  const percentage = `${decimalNumber * 100}%`;
+// function convertToPercentage(decimalNumber) {
+//   const decimalNumber = 0.5;
+//   const percentage = `${decimalNumber * 100}%`;
 
-  return percentage;
-}
+//   return percentage;
+// }
 
-console.log(decimalNumber);
+// console.log(decimalNumber);
 
 // =============> write your explanation here
+// The program did not return undefined on first call, but rather returned an identifier redeclaration syntaxerror. However when corrected without variable redeclaration, it returns undefined because console.log(decimalNumber) is not defined.
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+console.log(convertToPercentage(0.5));

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

@@ -1,20 +1,28 @@
 
 // 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;
-}
+// // This code would throw a syntaxerror "missing valid function parameter".
+// function square(3) {
+//     return num * num;
+// }
 
 // =============> write the error message here
+// function square(3) {
+//                 ^
 
+// SyntaxError: Unexpected number
 // =============> explain this error message here
+// The JavaScript exception "missing formal parameter" occurs when your function declaration is missing valid parameters.
+// In the declaration of a function, the parameters must be identifiers, not any value like numbers, strings, or objects.
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
-
+function square(num) {
+  return num * num;
+}
+console.log(square(10));

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

@@ -1,14 +1,20 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+// This function only logs the evaluation and would compile as undefined when called
 
-function multiply(a, b) {
-  console.log(a * b);
-}
+// function multiply(a, b) {
+//   console.log(a * b);
+// }
 
-console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+// console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
-
+// The function does not have a return statement, it only logs the evaluation inside the function, but calling the function without a return statement would not return the evaluation. it would return undefined
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function multiply(a, b) {
+  return a * b;
+}
+
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);

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

@@ -1,13 +1,19 @@
 // Predict and explain first...
 //  =============> write your prediction here
+// The function would return undefined
+// function sum(a, b) {
+//   return;
+//   a + b;
+// }
 
-function sum(a, b) {
-  return;
-  a + b;
-}
-
-console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+// console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+// When a return statement is used in a function body, the execution of the function is stopped, therefore, evaluation a+b cannot be reached.
 // Finally, correct the code to fix the problem
 //  =============> write your new code here
+function sum(a, b) {
+  return a + b;
+}
+
+console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);

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

@@ -2,23 +2,36 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+// The function will always return 3
 
-const num = 103;
+// const num = 103;
 
-function getLastDigit() {
-  return num.toString().slice(-1);
-}
+// function getLastDigit() {
+//   return num.toString().slice(-1);
+// }
 
-console.log(`The last digit of 42 is ${getLastDigit(42)}`);
-console.log(`The last digit of 105 is ${getLastDigit(105)}`);
-console.log(`The last digit of 806 is ${getLastDigit(806)}`);
+// console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+// console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+// console.log(`The last digit of 806 is ${getLastDigit(806)}`);
 
 // Now run the code and compare the output to your prediction
 // =============> write the output here
 // Explain why the output is the way it is
 // =============> write your explanation here
+//getLastDigit takes no parameters.
+//Inside the function, will always return the last digit of the global variable num, which is "3".
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+//Every call ignores the number that is passed in the argument and just returns "3"
+
+function getLastDigit(num) {
+  return num.toString().slice(-1);
+}
+
+console.log(`The last digit of 42 is ${getLastDigit(42)}`);
+console.log(`The last digit of 105 is ${getLastDigit(105)}`);
+console.log(`The last digit of 806 is ${getLastDigit(806)}`);

Sprint-2/3-mandatory-implement/1-bmi.js

@@ -15,5 +15,10 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-    // return the BMI of someone based off their weight and height
-}
+  // return the BMI of someone based off their weight and height
+  const bmi = weight / (height * height);
+  const convertedBmi = Number(bmi.toFixed(1));
+  return convertedBmi;
+}
+console.log(calculateBMI(70, 1.73));
+console.log(typeof calculateBMI());

Sprint-2/3-mandatory-implement/2-cases.js

@@ -14,3 +14,9 @@
 // You will need to come up with an appropriate name for the function
 // Use the MDN string documentation to help you find a solution
 // This might help https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/toUpperCase
+
+function toUpperSnakeCase(str) {
+  const strTransform = str.replaceAll(" ", "_").toUpperCase();
+  return strTransform;
+}
+console.log(toUpperSnakeCase("lord of the rings"));

Sprint-2/3-mandatory-implement/3-to-pounds.js

@@ -4,3 +4,26 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+
+function toPounds(penceString) {
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  );
+
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  );
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+
+  return `£${pounds}.${pence}`;
+}
+console.log(toPounds("3p"));
+console.log(toPounds("399p"));
+console.log(toPounds("3999999p"));
+console.log(toPounds("3999999999999999p"));

Sprint-2/4-mandatory-interpret/time-format.js

@@ -10,6 +10,7 @@ function formatTimeDisplay(seconds) {
 
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
+console.log(formatTimeDisplay(61));
 
 // You will need to play computer with this example - use the Python Visualiser https://pythontutor.com/visualize.html#mode=edit
 // to help you answer these questions
@@ -18,17 +19,21 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// pad() is called 3 Times whenever formatTimeDisplay() is called.
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
-
 // b) What is the value assigned to num when pad is called for the first time?
 // =============> write your answer here
+// The first call to pad() is "0", for totalHours which is "0"
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+// The return value is "00"
 
 // d) What is the value assigned to num when pad is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+// 1: -> pad() was called from line 11. Given that num is "0", the first call to pad() (for totalHours which is "0"). There were two more calls to pad()(for remainingLastMinutes and remaining LastSeconds) and the value assigned to num for the last call is "0"
 
 // e) What is the return value assigned to num when pad is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+//01 -> Given that num is 1, the last call to pad() (for remainingSeconds is 1) and the return value is "01"