London | 26-ITP-May | Talia Kucuk | Sprint 2 | Courswork-Sprint2

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

@@ -1,13 +1,20 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> I believe an error will occur as the same variable name has been declared twice.
 
 // 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
+// =============> When running the code there was an error message saying 'Identifier 'str' has already been declared.
+// This lets us know that the identifier - which is the name of the variable str - has been declared more than once. The error occurs as the same variable name - str - is being declared twice which is not allowed. 
+// I would personally fix this by changing the variable name of the second declaration. 
+// I tested this and didn't get a capitalised result - I realised this was because I hadn't also changed the variable name after 'return' - this was still str so I changed it to capitalised and now it works.
 // =============> write your new code here
+function capitalise(str) {
+  let capitalised = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalised;
+};

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

@@ -1,20 +1,28 @@
 // Predict and explain first...
 
 // Why will an error occur when this program runs?
-// =============> write your prediction here
+// =============> There are two errors I notice here. The first is that, similarly to the first exercise, the variable decimalNumber is being declared twice - first as the parameter of the function and then again with const decimalNumber.
+// JavaScript does not allow for a variable to be declared more than once.
+// The second error is the console.log section where it attempts to access a variable inside the function which will not work. The function is what needs to be called.
 
 // Try playing computer with the example to work out what is going on
 
 function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
-
   return percentage;
 }
 
 console.log(decimalNumber);
 
-// =============> write your explanation here
+// =============> As the decimalNumber variable has already been declared within the function I removed the second const declaration as it is unnecessary.
+// I changed the console.log section to call the function and not the variable. I then tested this and got the expected result.
 
 // 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(0.3));

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

@@ -3,18 +3,23 @@
 
 // this function should square any number but instead we're going to get an error
 
-// =============> write your prediction of the error here
-
+// =============> The first error I see is the number 3 as the parameter inside the function. This is the error that JavaScript will flag as the parameter needs to be a variable name.
+// The second error I noticed is num + num - what is num? JavaScript will not know as it has not been declared.
 function square(3) {
     return num * num;
 }
 
-// =============> write the error message here
 
-// =============> explain this error message here
+// =============> SyntaxError: Unexpected number
+
+// =============> As I expected JavaScript has flagged the use of a number as the function parameter, as it needs to be a variable name. 
 
 // Finally, correct the code to fix the problem
 
-// =============> write your new code here
+// =============> 
+
+function square(num) {
+return num * num;
+}
 
 

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

@@ -1,14 +1,19 @@
 // Predict and explain first...
 
-// =============> write your prediction here
+// =============> Right now the first console.log inside the function prints 320 - but the function does not have a return statement, so when it is used inside the template literal it will show as undefined. The code should use return a * b instead of 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)}`);
 
-// =============> write your explanation here
+// =============> This code returned "The result of multiplying 10 and 32 is undefined" as predicted because there is no return statement within the function.
 
 // 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, 21)}`)

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

@@ -1,5 +1,5 @@
 // Predict and explain first...
-//  =============> write your prediction here
+//  =============> As there is a ; after return this means this function will return 'undefined' as it will not be able to run a + b. There is no value after return. The console.log statement will be The sum of 10 and 32 is undefined.
 
 function sum(a, b) {
   return;
@@ -8,6 +8,9 @@ function sum(a, b) {
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
-// =============> write your explanation here
+// =============> As predicted the console.log statement returned The sum of 10 and 32 is undefined. To fix this I will remove the ; after return so that the function can return the sum of a + b
 // Finally, correct the code to fix the problem
-//  =============> write your new code here
+//  =============> 
+function sum(a, b) {
+  return a + b;
+}

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

@@ -1,8 +1,7 @@
 // Predict and explain first...
 
 // Predict the output of the following code:
-// =============> Write your prediction here
-
+// =============> Num has been declared as 103. The function converts the number to a string and then returns the last number of that string. The return statement specifies the last digit of num which is already declared as 103 - so no matter what number someone puts in the temperate literals within the console.log statements 3 is always going to be returned.
 const num = 103;
 
 function getLastDigit() {
@@ -14,11 +13,15 @@ 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 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
+// =============> As predicted, 3 is always going to be returned as the num was specified as 103 and the parameter within the function was not declared. To fix this const num = 103 needs to be removed and the variable num needs to be placed as a parameter within the function getLastDigit
 // Finally, correct the code to fix the problem
-// =============> write your new code here
+// =============>
+  function getLastDigit(num) {
+return num.toString().slice(-1);
+  }
 
 // This program should tell the user the last digit of each number.
 // Explain why getLastDigit is not working properly - correct the problem

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

@@ -15,5 +15,12 @@
 // 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
-}
+    const heightSquared = height * height;
+    const bmi = weight / heightSquared;
+    const bmiMultiplyByTen = bmi * 10;
+    const bmiRounded = Math.round(bmiMultiplyByTen);
+    const finalBmi = bmiRounded / 10;
+    return finalBmi;
+}
+
+console.log(calculateBMI(58, 1.52));

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

@@ -14,3 +14,11 @@
 // 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) {
+    str = str.toUpperCase();
+    str = str.replaceAll(" ", "_");
+    return str
+}
+
+console.log(toUpperSnakeCase("harry potter and the philosopher's stone"));

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) {
+
+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("13200p"))
+
+// removed the unchanging const variable of 399p so we can have various inputs 
+// added a function with the variable name as the parameter
+// changed console.log to return so that it's more reusable

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

@@ -15,24 +15,26 @@ 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
 
 // Questions
 
 // 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
+// =============> 0 is the value assigned to num as the first pad is totalhours which calculates to be 0
 
 // c) What is the return value of pad is called for the first time?
-// =============> write your answer here
+// =============> "00" - this is because it has been stated within the function that if the value's length is less than 2 which 0 is, then add another 0 at the beginning ("0" + numString;). Also toString converts 0 from a number to a string which is why I included ""
 
 // 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 last pad is remainingSeconds which is 1 so the value assigned to num is 1
 
 // 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
+// =============> "01" - same logic as quested c. Also as "01" is not shorter than length of 2 the loop closes and doesn't run again