London | 26 ITP SEP | Russom Gebremeskel | Sprint 3 | Coursework

Sprint-3/1-key-errors/0.js

@@ -1,6 +1,10 @@
 // Predict and explain first...
 //  =============> write your prediction here
 
+// Prediction: the method toUpperCase return the character at index 0 of str as uppercase.
+// slice method will return the characters of str starting at index 1 excluding the first character.
+// the template literal combines the converted upper case first character and the rest of the string.
+
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
@@ -10,4 +14,12 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
+
+// Explanation: 1. str declares twice.Hence it gives syntax error.
+// Refactor:    2. instead of returning str return can directly send back the template literal expression. 
+
 // =============> write your new code here
+
+function capitalise(str) {
+  return `${str[0].toUpperCase()}${str.slice(1)}`;  
+}

Sprint-3/1-key-errors/1.js

@@ -3,6 +3,9 @@
 // Why will an error occur when this program runs?
 // =============> write your prediction here
 
+// Prediction:
+// 1. decimalNumber is declared twice and it will give syntax error.
+
 // Try playing computer with the example to work out what is going on
 
 function convertToPercentage(decimalNumber) {
@@ -16,5 +19,16 @@ console.log(decimalNumber);
 
 // =============> write your explanation here
 
+// 2. console.log will return undefined as decimalNumber local scope declaration inside the function.
+// 3. It's percentage not decimalNumber needs printing.
+
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  return `${decimalNumber * 100}%`;
+}
+
+console.log(convertToPercentage(0.5));
+
+// The function convertToPercentage can be called passing with an argument of the input.

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

@@ -5,16 +5,30 @@
 
 // =============> write your prediction of the error here
 
+// Prediction:
+// 1. This will give reference error.
+// 
+
+
 function square(3) {
     return num * num;
 }
 
 // =============> write the error message here
+// 
+// SyntaxError: Unexpected number
 
 // =============> explain this error message here
 
+// The function expects a parameter name and it shouldn't start with a number.
+// num should be the parameter and later 3 can be passed as an argument.
+
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
+function square(num) {
+    return num * num;
+}
+
 

Sprint-3/2-mandatory-debug/0.js

@@ -2,6 +2,8 @@
 
 // =============> write your prediction here
 
+// 'The result of multiplying 10 and 32 is 10 * 32' is printed.
+
 function multiply(a, b) {
   console.log(a * b);
 }
@@ -10,5 +12,13 @@ console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
 
 // =============> write your explanation here
 
+// the function prints a * b. When presented with multiply(10, 32) it prints 10 * 32.
+
 // 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-3/2-mandatory-debug/1.js

@@ -1,6 +1,8 @@
 // Predict and explain first...
 //  =============> write your prediction here
 
+// it will return syntax error
+
 function sum(a, b) {
   return;
   a + b;
@@ -9,5 +11,16 @@ 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
+
+// There is a semicolon after return.
+
+// Finally, correct the code to fix the problem.
+// Later I discovered having a line between return and a + b gives another undefined error message
 //  =============> 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-3/2-mandatory-debug/2.js

@@ -3,6 +3,10 @@
 // Predict the output of the following code:
 // =============> Write your prediction here
 
+// The last digit of 42 is 3 undefined
+// The last digit of 105 is 3 undefined
+// The last digit of 806 is 3 undefined
+
 const num = 103;
 
 function getLastDigit() {
@@ -15,10 +19,31 @@ 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
+
+//The last digit of 42 is 3
+//The last digit of 105 is 3
+//The last digit of 806 is 3
+
 // Explain why the output is the way it is
 // =============> write your explanation here
+
+// Because the function is not given a parameter and it is being passed an argument the same time which it ignores. 
+// The function uses the global variable num instead and print 3
+
 // Finally, correct the code to fix the problem
+
 // =============> write your new code here
 
+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)}`);
+
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem
+
+// The reason was the num variable wasn't declared as a parameter inside the function. 
+// At the same time the function is receiving arguments which the function ignores.

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

@@ -14,6 +14,7 @@
 // Then when we call this function with the weight and height
 // It should return a string of their Body Mass Index to 1 decimal place
 
+
 function calculateBMI(weight, height) {
-  // return the BMI of someone based off their weight and height
-}
+   return (weight / (height * height)).toFixed(1); 
+}

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

@@ -14,3 +14,7 @@
 // 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) {
+    return str.toUpperCase().replaceAll(" ", "_");
+}

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

@@ -4,3 +4,16 @@
 // 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 toPound(priceInPence) {
+  const penceDigits = priceInPence
+    .substring(0, priceInPence.length - 1)
+    .padStart(3, "0");
+
+  const poundsPart = penceDigits.substring(0, penceDigits.length - 2);
+
+  const pencePart = penceDigits.substring(penceDigits.length - 2);
+
+  return `£${poundsPart}.${pencePart}`;
+}
+console.log(toPound("399p"));

Sprint-3/4-mandatory-interpret/time-format.js

@@ -14,6 +14,7 @@ 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
@@ -23,16 +24,27 @@ function formatTimeDisplay(seconds) {
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
 
+// pad is called 3 times.
+
 // 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 value that assigned to num is 0
+
 // c) What is the return value of pad when it is called for the first time?
 // =============> write your answer here
 
+// The return value of pad 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
 
+// The value assigned to num is 1. This is because 1 is the last character in the string 61
+
 // e) What is the return value of pad when it is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+
+// The return value is "01". when pad is called for the last time it takes the last character of the string 61.
+// After checking remainingSeconds length which is less than 2 it adds a "0" and returns "01"

Sprint-3/5-stretch-extend/format-time.js

@@ -4,22 +4,83 @@
 
 function formatAs12HourClock(time) {
   const hours = Number(time.slice(0, 2));
+  const minutes = time.slice(3, 5);
+
+  if (hours === 0) {
+    return `12:${minutes} AM`;
+  }
+  if (hours === 12) {
+    return `12:${minutes} PM`;
+  }
   if (hours > 12) {
-    return `${hours - 12}:00 pm`;
+    return `${hours - 12}:${minutes} PM`;
   }
-  return `${time} am`;
+  return `${time} AM`;
 }
 
-const currentOutput = formatAs12HourClock("08:00");
-const targetOutput = "08:00 am";
+const currentOutput1 = formatAs12HourClock("00:00");
+const targetOutput1 = "12:00 AM";
 console.assert(
-  currentOutput === targetOutput,
-  `current output: ${currentOutput}, target output: ${targetOutput}`
+  currentOutput1 === targetOutput1,
+  `current output 1: ${currentOutput1}, target output: ${targetOutput1}`,
 );
 
-const currentOutput2 = formatAs12HourClock("23:00");
-const targetOutput2 = "11:00 pm";
+const currentOutput2 = formatAs12HourClock("00:01");
+const targetOutput2 = "12:01 AM";
 console.assert(
   currentOutput2 === targetOutput2,
-  `current output: ${currentOutput2}, target output: ${targetOutput2}`
+  `current output 2: ${currentOutput2}, target output: ${targetOutput2}`,
+);
+
+const currentOutput3 = formatAs12HourClock("08:00");
+const targetOutput3 = "08:00 AM";
+console.assert(
+  currentOutput3 === targetOutput3,
+  `current output 3: ${currentOutput3}, target output: ${targetOutput3}`,
+);
+
+const currentOutput4 = formatAs12HourClock("12:00");
+const targetOutput4 = "12:00 PM";
+console.assert(
+  currentOutput4 === targetOutput4,
+  `current output 4: ${currentOutput4}, target output: ${targetOutput4}`,
+);
+
+const currentOutput5 = formatAs12HourClock("12:01");
+const targetOutput5 = "12:01 PM";
+console.assert(
+  currentOutput5 === targetOutput5,
+  `current output 5: ${currentOutput5}, target output: ${targetOutput5}`,
 );
+
+const currentOutput6 = formatAs12HourClock("13:00");
+const targetOutput6 = "1:00 PM";
+console.assert(
+  currentOutput6 === targetOutput6,
+  `current output 6: ${currentOutput6}, target output: ${targetOutput6}`,
+);
+
+const currentOutput7 = formatAs12HourClock("23:00");
+const targetOutput7 = "11:00 PM";
+console.assert(
+  currentOutput7 === targetOutput7,
+  `current output 7: ${currentOutput7}, target output: ${targetOutput7}`,
+);
+
+const currentOutput8 = formatAs12HourClock("23:59");
+const targetOutput8 = "11:59 PM";
+console.assert(
+  currentOutput8 === targetOutput8,
+  `current output 8: ${currentOutput8}, target output: ${targetOutput8}`,
+);
+
+// Edge test cases tested for:
+
+// 1) 00:00 -> 12:00 AM
+// 2) 00:01 -> 12:01 AM
+// 3) 08:00 -> 08:00 am
+// 4) 12:00 -> 12:00 PM
+// 5) 12:01 -> 12:01 PM
+// 6) 13:00 -> 1:00 PM
+// 7) 23:00 -> 11:00 PM
+// 8) 23:59 -> 11:59 PM