NW-ITP |Mohammed Alzaki | Module-Structuring-and-Testing-Data| Sprint2 | week4

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

@@ -1,13 +1,23 @@
 // Predict and explain first...
 //  =============> write your prediction here
-
+//The variable str has been declared twice the first one as the function
+//  and the second time inside the function =>   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
 // call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
-function capitalise(str) {
+/* function capitalise(str) {
   let str = `${str[0].toUpperCase()}${str.slice(1)}`;
   return str;
-}
+} */
 
 // =============> write your explanation here
+// An error occured => SyntaxError: Identifier 'str' has already been declared
+//because in javascript we cant declare a variable more than once within scope .
+
 // =============> write your new code here
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+   return str;
+ }
+
+ console.log(capitalise("cool"))

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

@@ -2,19 +2,33 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
-
+//// The variable decimalNmber has been declared twice once as a parameter for convertToPercentage
+// function and the second time inside the function
 // 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);
+console.log(decimalNumber); */
 
 // =============> write your explanation here
+//The function convertToPercentage(decimalNumber) accepts a parameter decimalNumber
+//Inside the function, ywe have decimalNumber redeclared using const decimalNumber = 0.5;, which creates a conflict
+// Finally, correct the code to fix the problem
+//we should remove the redeclaration of decimalNumber inside the function. Instead, use the parameter directly.and then
+//pass a decimal number as input => 0.5 in the function call
 
 // Finally, correct the code to fix the problem
 // =============> write your new code here
+
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+  return percentage;
+}
+
+const result = convertToPercentage(0.5); 
+console.log(result); // Output => "50%"

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

@@ -4,17 +4,25 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+// The number three was passed straight to the function witch is why it's throwing an error
 
-function square(3) {
+/* function square(3) {
     return num * num;
 }
-
+ */
 // =============> write the error message here
+// Error message => SyntaxError: Unexpected number
 
 // =============> explain this error message here
+//The function was expecting a parameter and got a number instead and a number 
+// can not be a valid parameter name
+//We pass 3 as an argument when calling square(3), and the function returns 9 (since 3 squared is 9).
 
 // Finally, correct the code to fix the problem
 
 // =============> write your new code here
 
-
+function square(num) {
+    return num * num;
+}
+console.log(square(3))

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

@@ -1,14 +1,23 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+//In this function console.log() is used instead of return
 
-function multiply(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
-
+//By using console.log() this multiply function dose not return anything and it just printing the output 
+//of => a * b to the console + undefined => since console.log does not return
 // Finally, correct the code to fix the problem
+// 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 +1,24 @@
 // Predict and explain first...
 //  =============> write your prediction here
+//Here we have return; and => a + b ; in seprate lines closed with semicolon.
 
-function sum(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
+//AS we know that return end and stops the execution of the function witch mean that => a + b
+//will not be executed and line 8 is useless since the function stops at line 7.
+
 // 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

@@ -1,9 +1,12 @@
 // Predict and explain first...
+// The constant variable num is set to = 103 ,and num should be passed as a parameter to getLastDigit function
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+/* The last digit will be the same for all values that will be passed to it 
+since it coming from the constant.*/
 
-const num = 103;
+/* const num = 103;
 
 function getLastDigit() {
   return num.toString().slice(-1);
@@ -12,13 +15,33 @@ 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 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
+//The output is the same because it coming from the execution of =>  num.toString().slice(-1);
+//=> 3 over and over again
+
 // 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
+// To correct the code we needed to get rid of => const num = 103
+//and pass num as a parameter to the function and now it giving the proper output
+/* The last digit of 42 is 2
+The last digit of 105 is 5
+The last digit of 806 is 6 */

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

@@ -15,5 +15,11 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
+    let squared = height * height;
+    let bmi = weight/squared ;
+    let bmiRounded =  Math.round(bmi * 10) / 10;
+    return bmiRounded ;
     // return the BMI of someone based off their weight and height
-}
+}
+
+console.log(calculateBMI(70,1.73))

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

@@ -14,3 +14,10 @@
 // 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.replace(/\s+/g, '_').toUpperCase();
+  }
+
+  console.log(toUpperSnakeCase("hello there")); 
+  console.log(toUpperSnakeCase("lord of the rings")); 

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

@@ -4,3 +4,25 @@
 // 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("399p"))

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 +19,26 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+/* The pad function is called three times inside the formatTimeDisplay function:
+Once for totalHours => to pad the hour value.
+Once for remainingMinutes => to pad the minutes value.
+Once for remainingSeconds =>to pad the seconds value. */
 
 // 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
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+//"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 last time pad is called is for remainingSeconds, which is calculated as remainingSeconds = 61 % 60 = 1 when formatTimeDisplay(61) is called.
 
 // 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 last call to pad is for remainingSeconds, which is 1. The padStart(2, "0") will pad this number to make it two digits.
+//And return value =>"01"