London | 26-ITP_May | Vito Moratti | Sprint 2 | Coursework/sprint 2

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

@@ -1,7 +1,9 @@
 // Predict and explain first...
 //  =============> write your prediction here
-
-// call the function capitalise with a string input
+// Well, I think the variable "str" is being declared twice, so the code will
+//  through an error message.
+//
+//call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
 function capitalise(str) {
@@ -10,4 +12,12 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
+//The variable "str" has been used as a parameter for the capitalise function
+//and also been declared again inside the function. I think if "let" is removed
+//the code will work.
 // =============> write your new code here
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return str;
+}
+console.log(capitalise("sorted"));

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

@@ -1,20 +1,40 @@
 // Predict and explain first...
-
 // Why will an error occur when this program runs?
 // =============> write your prediction here
-
+// I think there will be an error as "decimalNumber" variable has already been declared as a parameter in
+// "convertToPercentage" function
+// 
 // Try playing computer with the example to work out what is going on
 
-function convertToPercentage(decimalNumber) {
+/*function convertToPercentage(decimalNumber) {
   const decimalNumber = 0.5;
   const percentage = `${decimalNumber * 100}%`;
 
   return percentage;
 }
 
-console.log(decimalNumber);
+console.log(decimalNumber); */
 
 // =============> write your explanation here
+// =============Explanation ===============
+// the "decimalNumber" variable is a local variable and can only be seen inside "convertToPercentage" function
+// therefore when called outside the function it triggers "ReferenceError"
 
 // Finally, correct the code to fix the problem
+// =========correction=========
+// problem can be fixed by moving the variable declaration outside the function
+//  and making it global
+
 // =============> write your new code here
+
+const decimalNumber = 0.5;
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(decimalNumber);
+console.log(convertToPercentage(decimalNumber));
+
+

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

@@ -1,20 +1,24 @@
-
 // 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) {
+//=========Prediction=============
+// I think there will not be en error till we call the function.
+/*function square(num) {
     return num * num;
 }
-
+console.log(square(5))*/
 // =============> write the error message here
-
+// Unexpected number
 // =============> explain this error message here
-
+// I think it function expects parameter as a variable rather than  a number.
 // Finally, correct the code to fix the problem
-
+// ===========correction=========
+// to correct the code we need to introduce parameter as a variable, rather than a number.
+// that way any number can be passed when function is called.
 // =============> write your new code here
-
-
+function square(num) {
+  return num * num;
+}
+console.log(square(5));

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

@@ -1,14 +1,25 @@
 // Predict and explain first...
 
 // =============> write your prediction here
-
-function multiply(a, b) {
+//===========Prediction=======
+// I think the code will not produce the desired result as the function is not returning any value
+/*function multiply(a, b) {
   console.log(a * b);
 }
-
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+console.log(multiply(3, 5));
+typeof(multiply(3, 4));*/
 
 // =============> write your explanation here
-
+//===============Explanation=========
+// The function itself prints out the result, but the result has no (type) as such and can not be used as
+// a data type. 
+//
 // Finally, correct the code to fix the problem
+//============correction============
+// To correct the code "return" needs to be introduced.
 //  =============> 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 +1,23 @@
 // Predict and explain first...
 //  =============> write your prediction here
-
+// =============explanation==========
+// I think will either give error, or no result at all as there is  a ";" semicolon after
+//  the return statement and the actual calculation is not assigned to anything.
 function sum(a, b) {
   return;
-  a + b;
+   a + b;
 }
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+//==============Explanation===============
+//To fix the code the ";" must be removed, and the calculation 
+//needs to be placed next to the "return"
 // 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

@@ -2,6 +2,9 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+//============Prediction========
+// I think the code output will be  "3" in al three cases as "num variable is declared outside the function and 
+// not used as a parameter for the function"
 
 const num = 103;
 
@@ -14,11 +17,30 @@ 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
+// prediction matched
 // =============> 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
+//===============Explanation===========
+// The variable is not used as a parameter of the function, and therefore
+//  is ignored when passed inside function call.
 // Finally, correct the code to fix the problem
+//
 // =============> write your new code here
+//const num = 103;
 
+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
+// =============explanation==================
+// The variable is not used as a parameter of the function, and therefore
+//  is ignored when passed inside function call.