Birmingham | 25-ITP-Sep | Baba Yusuf | Sprint 2 | Module-Structuring-and-Testing-Data

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

@@ -3,11 +3,19 @@
 
 // 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;
 }
-
+*/
 // =============> write your explanation here
+/*Undeclared variables are automatically declared when first used. As a parameter in the 'capitalise' function,
+ 'str' is already declared. trying to declare it again with 'let' will cause a syntax error.
+*/
 // =============> write your new code here
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return str;
+}
+console.log(capitalise("hello world")); // This line is inserted only to test the code. It returns "Hello world"

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

@@ -4,7 +4,7 @@
 // =============> 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}%`;
@@ -13,8 +13,20 @@ function convertToPercentage(decimalNumber) {
 }
 
 console.log(decimalNumber);
-
+*/
 // =============> write your explanation here
-
+/*
+1. Undeclared variables are automatically declared when first used. As a parameter in the 'convertToPercentage' function,
+'decimalNumber' is (automatically) already declared. trying to declare it again with 'const' causes a syntax error.
+2. Also, the 'console.log(decimalNumber);' line is outside the function, so 'decimalNumber' is not defined in that scope.
+3 decimalNumber = 0.5; overwrites the argument supplied, and so to make the function work as intended, this line should be removed, so the function does not ignore its input argument.
+*/
 // 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(0.25)); // This line is inserted only to test the code. It returns "25%"

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

@@ -1,20 +1,26 @@
-
 // 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
-
+// SyntaxError: Unexpected number
 // =============> explain this error message here
+/*
+1-The parameter name '3' is not a valid identifier. Function parameters names must (be valid variable names & not literal values), i.e. start with a letter, underscore (_), or dollar sign ($), and cannot be a number.
+2-Also, the function uses 'num' which is not defined anywhere. It should use the parameter name instead.
+3-Finally, the function is not called anywhere, so it won't produce any output.
+*/
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
-
-
+function square(num) {
+  return num * num;
+}
+console.log(square(3)); // This line is inserted only to test the function. It returns 9

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

@@ -1,14 +1,27 @@
 // Predict and explain first...
-
+/*
+The function 'multiply' does not return any value, it only logs the product of 'a' and 'b' to the console, within itself. 
+Therefore, when we try to use its result in a template literal, it will be 'undefined'.
+In the below, i expect the TWO outputs to be, 320 and The result of multiplying 10 and 32 is undefined.
+*/
 // =============> write your prediction here
-
+/*
 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
-
+/*
+1. I will change the function to return the product of 'a' and 'b' instead of logging it. 
+This way, when we call 'multiply(10, 32)', it will return 320,
+ which can then be used in the template literal.
+*/
 // 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 +1,29 @@
 // Predict and explain first...
-//  =============> write your prediction here
 
+//  =============> write your prediction here
+/*
+The function 'sum' does not return the sum of 'a' and 'b' because there is a semicolon immediately after the 'return' statement.
+This causes the function to return 'undefined' instead of the intended sum.
+*/
+/*
 function sum(a, b) {
   return;
   a + b;
 }
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
-
+*/
 // =============> write your explanation here
+/*
+1. In JavaScript, when a 'return' statement is followed by a newline, it is treated as if there is a semicolon immediately after 'return'.
+2. This means that the function exits at the 'return' statement and does not execute the next line, which contains the actual sum operation.
+3. As a result, the function returns 'undefined' instead of the sum of 'a' and 'b'.
+4. To fix this, we need to place the expression to be returned on the same line as the 'return' statement.
+*/
 // 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

@@ -1,8 +1,19 @@
 // Predict and explain first...
+/*
+The function 'getLastDigit' is not working properly because it does not take any parameters, yet it is being called with arguments (42, 105, 806).
+As a result, it always returns the last digit of the constant 'num', which is 103, instead of the last digit of the numbers passed to it.
+*/
+//  =============> write your prediction here
 
+/*
+ The output will be:
+ The last digit of 42 is 3
+ The last digit of 105 is 3
+ The last digit of 806 is 3
+*/
 // Predict the output of the following code:
 // =============> Write your prediction here
-
+/*
 const num = 103;
 
 function getLastDigit() {
@@ -12,13 +23,32 @@ function getLastDigit() {
 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
+/*
+The output is:
+ 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
+/*  1. The function 'getLastDigit' does not accept any parameters, so it does not use the values (42, 105, 806) passed to it when called.
+    2. Instead, it always operates on the constant 'num', which is set to 103.
+    3. The function converts 'num' to a string and retrieves the last character using 'slice(-1)', which is '3'.
+    4. Therefore, regardless of the input values, the function always returns '3', leading to the same output for all calls.
+*/
 // =============> write your explanation here
 // 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
+
+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);
+  return parseFloat(bmi.toFixed(1));
+}
+console.log(calculateBMI(70, 1.73)); // This line is inserted only to test the function. It returns 23.4
+console.log(calculateBMI(80, 1.8)); // This line is inserted only to test the function. It returns 24.7
+console.log(calculateBMI(90, 1.75)); // This line is inserted only to test the function. It returns 29.4

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) {
+  // return the string in UPPER_SNAKE_CASE
+  return str.toUpperCase().replace(/ /g, "_");
+}
+console.log(toUpperSnakeCase("hello there")); // This line is inserted only to test the function. It returns "HELLO_THERE"
+console.log(toUpperSnakeCase("lord of the rings")); // This line is inserted only to test the function. It returns "LORD_OF_THE_RINGS"

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

@@ -4,3 +4,28 @@
 // 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) {
+  // Convert a string representing an amount in pence (e.g., "123p") to pounds and pence format (e.g., "£1.23")
+
+  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("5555p")); // This line is inserted only to test the function. It returns "£55.55"
+console.log(toPounds("399p")); // This line is inserted only to test the function. It returns "£0.05"
+console.log(toPounds("50p")); // This line is inserted only to test the function. It returns "£0.50"
+console.log(toPounds("500p")); // This line is inserted only to test the function. It returns "£5.00"

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

@@ -10,25 +10,36 @@ function formatTimeDisplay(seconds) {
 
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
+console.log(formatTimeDisplay(61)); // This line is inserted only to test the function. It returns "00:01:01"
 
+// Here is a function that takes a number of seconds and returns a string formatted as "HH:MM:SS"
 // 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
 
 // Questions
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
-
+//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
-
+//61
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
-
+//0
 // 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 when pad is called for the last time is 1.
+The last call to pad in the template literal is pad(remainingSeconds). Since remainingSeconds = 61 % 60 = 1, the value passed to num is 1. This will return "01" after padding, resulting in the final output "00:01:01"
+*/
 // 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
+/*
+The return value of the last call to pad is "01".
+Explanation: When pad is called with remainingSeconds (which equals 1), the parameter num receives the value 1. The function then converts it to a string "1", 
+pads it to 2 characters with leading zeros to get "01", and returns this string. This returned value "01" 
+is then inserted into the template literal as the last part of the time display, producing the final output "00:01:01".
+*/

Sprint-2/5-stretch-extend/format-time.js

@@ -23,3 +23,49 @@ console.assert(
   currentOutput2 === targetOutput2,
   `current output: ${currentOutput2}, target output: ${targetOutput2}`
 );
+console.log(formatAs12HourClock("12:00")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("12:01")); // This line is inserted only to test the function. It returns "12:00 pm"
+console.log(formatAs12HourClock("13:13")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("00:01")); // This line is inserted only to test the function. It returns "12:00 pm"
+console.log(formatAs12HourClock("01:01")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("11:59")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("24:00")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("14:14")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("20:20")); // This line is inserted only to test the function. It returns "12:00 am"
+console.log(formatAs12HourClock("00:00")); // This line is inserted only to test the function. It returns "12:00 am"
+
+/*
+Test Groups Created:
+1. Midnight (00:xx) - Edge case for start of day
+2. Morning hours (01-11) - Standard AM times
+3. Noon (12:xx) - Edge case for 12 PM
+4. Afternoon/Evening (13-23) - Standard PM times requiring conversion
+5. Minutes preservation - Ensures minutes aren't lost
+
+Bugs Found:
+1. Midnight bug: "00:00" returns "00:00 am" instead of "12:00 am"
+2. Noon bug: "12:00" returns "12:00 am" instead of "12:00 pm"
+3. Minutes lost: All times lose their minutes and show :00 (e.g., "13:13" becomes "1:00 pm" instead of "1:13 pm")
+4. Leading zeros: Morning times keep the input format including leading zeros
+*/
+
+/* 
+function formatAs12HourClock(time) {
+  const hours = Number(time.slice(0, 2));
+  const minutes = time.slice(3, 5);
+
+  if (hours === 0) {
+    // Midnight: 00:xx becomes 12:xx am
+    return `12:${minutes} am`;
+  } else if (hours < 12) {
+    // Morning: 1-11 stays same with am
+    return `${hours}:${minutes} am`;
+  } else if (hours === 12) {
+    // Noon: 12:xx stays 12:xx pm
+    return `12:${minutes} pm`;
+  } else {
+    // Afternoon/Evening: 13-23 subtract 12 and add pm
+    return `${hours - 12}:${minutes} pm`;
+  }
+}
+*/