Glasgow| 25-ITP-Sep | Abraham-Habte| Sprint 2 | Coursework/Sprint 2

Sprint-1/1-key-exercises/1-count.js

@@ -4,3 +4,7 @@ count = count + 1;
 
 // Line 1 is a variable declaration, creating the count variable with an initial value of 0
 // Describe what line 3 is doing, in particular focus on what = is doing
+Answer
+// Line 3; when we the right side first count in the right side is considered as 0 so 0+1 will be 1.
+// But the = sign does not mean the mathematical equal, its function is to take the result on the right and store it on the left.
+// Therefore if we write the same code in next line the result is not one but 2

Sprint-1/1-key-exercises/2-initials.js

@@ -5,7 +5,7 @@ let lastName = "Johnson";
 // Declare a variable called initials that stores the first character of each string.
 // This should produce the string "CKJ", but you must not write the characters C, K, or J in the code of your solution.
 
-let initials = ``;
+let initials = `${firstName[0]}${middleName[0]}${lastName[0]}`;
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

Sprint-1/1-key-exercises/3-paths.js

@@ -17,7 +17,9 @@ console.log(`The base part of ${filePath} is ${base}`);
 // Create a variable to store the dir part of the filePath variable
 // Create a variable to store the ext part of the variable
 
-const dir = ;
-const ext = ;
+const dir = filePath.slice(0, lastSlashIndex);
+const lastDotIndex = base.lastIndexOf(".");
+const ext = base.slice(lastDotIndex + 1);
+
 
 // https://www.google.com/search?q=slice+mdn

Sprint-1/1-key-exercises/4-random.js

@@ -7,3 +7,22 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 // Try breaking down the expression and using documentation to explain what it means
 // It will help to think about the order in which expressions are evaluated
 // Try logging the value of num and running the program several times to build an idea of what the program is doing
+
+// Answer
+
+// 1. 
+// The num in this scenario represent any integer between 1 and 100
+
+// 2.
+// Math.floor: rounds the number down to the nearest whole number which means it ignores the number to the right of the point. eg. 4.7=4
+// Math.random is a js code that returns any random number that is greater than or equal to 0 and less than 1
+//* is multiplication
+// maximum is the maximum given number, in this case 100
+//- is a subtraction
+// minimum is the minimum given number, in this case 1
+//(maximum - minimum +1) this is subtracting the minimum number from the maximum and add 1, in this case (100-1+1)=100
+//+ minimum: this turns the value by adding 1 to the whole equation. 
+
+//3.
+
+console.log(num)

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

@@ -1,2 +1,2 @@
-This is just an instruction for the first activity - but it is just for human consumption
-We don't want the computer to run these 2 lines - how can we solve this problem?
+//This is just an instruction for the first activity - but it is just for human consumption
+//We don't want the computer to run these 2 lines - how can we solve this problem?

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

@@ -1,4 +1,5 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+let age = 33;
 age = age + 1;
+console.log(age)

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

@@ -1,5 +1,6 @@
 // Currently trying to print the string "I was born in Bolton" but it isn't working...
 // what's the error ?
 
-console.log(`I was born in ${cityOfBirth}`);
+
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

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

@@ -7,3 +7,13 @@ const last4Digits = cardNumber.slice(-4);
 // Then run the code and see what error it gives.
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+
+//Answer
+
+// This code is not working because slice() is working with "string" or "arrays" but not with numbers. and cardNumber is a number.
+// So the error is "TypeError:cardNumber.slice is not a function"\
+// slice() didn't recognize the number as I expected before.
+
+const cardNumber = 4533787178994213;
+const last4Digits = String(cardNumber).slice(-4);
+console.log(last4Digits)

Sprint-1/2-mandatory-errors/4.js

@@ -1,2 +1,5 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+// the 12 and 24 are changing position 
+const 24HourClockTime = "20:53";
+const 12hourClockTime = "08:53";

Sprint-1/3-mandatory-interpret/1-percentage-change.js

@@ -13,10 +13,37 @@ console.log(`The percentage change is ${percentageChange}`);
 
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
 
+// There are five functions calls.
+//carPrice.replaceAll(",", "")
+//Number(carPrice.replaceAll(",", ""))
+//priceAfterOneYear.replaceAll("," "")
+//Number(priceAfterOneYear.replaceAll("," ""))
+//console.log(`The percentage change is ${percentageChange}`)
+
 // b) Run the code and identify the line where the error is coming from - why is this error occurring? How can you fix this problem?
 
+// When I run the code the error is "syntaxError: missing ) after argument list.
+// The error comes from line 5
+// The error occurs due to the missing coma between the two strings in the replaceAll() call.
+// Add coma between the two strings "priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));"
+
 // c) Identify all the lines that are variable reassignment statements
 
+// there are to lines that state variable reassignment
+// carPrice = Number(carPrice.replaceAll(",", ""));
+// priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+
 // d) Identify all the lines that are variable declarations
 
+// There are fore variable declarations (line 1, line 2, line 7, line 8)
+// let carPrice = "10,000";
+// let priceAfterOneYear = "8,543";
+// const priceDifference = carPrice - priceAfterOneYear;
+// const percentageChange = (priceDifference / carPrice) * 100;
+
+
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+
+// carprice at line 1 is a string in order to calculate for the next line of codes you have to change the string ti number.
+// carPrice.replaceAll(",","")). delete the coma in between the number (e.g from "10,000" to "10000")
+// number() change the string to number ("10000" to 10000)

Sprint-1/3-mandatory-interpret/2-time-format.js

@@ -12,14 +12,21 @@ console.log(result);
 // For the piece of code above, read the code and then answer the following questions
 
 // a) How many variable declarations are there in this program?
+// There are 6 variable declaration. "line1, line3, line4, line6, line7, line9"
 
 // b) How many function calls are there?
+// There is only one function call in this program "console.log(result);"
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// % is called remainder. There fore movieLength % 60 represents the remainder of the movie length after dividing by 60.
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// totalMinutes are calculated by subtracting the remaining seconds from movie length and divided by 60 to get full minutes. this helps to get a number which divided by 60 with out reminder.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// result represents the total length of the movie in the form of Hour: minute: second
+// moveDurationFormatted can be a better name to replace result. 
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// Yes it works for all value. the only thing that is concerning is the validation of movieLength as the negative integer also gives value which is unrealistic. 

Sprint-1/3-mandatory-interpret/3-to-pounds.js

@@ -1,4 +1,4 @@
-const penceString = "399p";
+onst penceString = "399p";
 
 const penceStringWithoutTrailingP = penceString.substring(
   0,
@@ -25,3 +25,13 @@ console.log(`£${pounds}.${pence}`);
 
 // To begin, we can start with
 // 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 2. const penceStringWithoutTrailingP = penceString.substring( 0, penceString.length - 1);
+//    This remove the p and left the string with only 399
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+//    this code make sure that the string has 3 character. since one pound is equal 100 pence.
+// 4. const pounds = paddedPenceNumberString.substring( 0, paddedPenceNumberString.length - 2);
+//    This code takes the number leaving the last 2 digits  "in this case it takes 3 and leave 99"
+// 5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2)  .padEnd(2, "0");
+//    This code takes the last digit from the string and also make sure that it has only two digits this gives a "99" value.
+// 6. console.log(`£${pounds}.${pence}`);
+//    his gives a result with £ sign and separated by . " in this case it gives £3.99 "

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

@@ -1,13 +1,27 @@
 // Predict and explain first...
 //  =============> write your prediction here
+
+// The code will capitalize the first word of the str which gives "Str"
 
 // 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;
-}
+// The error occurs in line 13 and it says "SyntaxError: Identifier 'str' has already been declared"
+// The error is informing us that the string str has already been declared in line 12 so we can not declare it again.
+
+//function capitalise(str) {
+//  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+//  return str;
+//}
 
 // =============> write your explanation here
+
+// The code is written to capitalize the first letter of str which is expected to give the result Str.
+
 // =============> write your new code here
+
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return str;
+}
+console.log(capitalise("str"))

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

@@ -2,19 +2,29 @@
 
 // Why will an error occur when this program runs?
 // =============> write your prediction here
+// This code is tend to be a code to convert decimal number in to %. I predict there will be an error because the call for the function has a bug.
 
 // 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
+// A syntaxError has been observed because the decimalNumber is already declared.
+// if we delete line 10 anther error happen this time about calling the function in which decimalNumber is not defined in the global scope.
 
 // 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("0.5"));

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

@@ -4,17 +4,26 @@
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
+/* There is a problem in the function parameter. we can not use number in parameter.
+even though line 12 by it self has no coding problem but the num is not declared before.*/
 
+/*
 function square(3) {
     return num * num;
 }
+*/
 
 // =============> write the error message here
-
+/* unexpected number
 // =============> explain this error message here
+we can not use number in a parameter so 3 is not used as identifier  */
 
 // 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 +1,21 @@
 // Predict and explain first...
 
 // =============> write your prediction here
+/*the function doesn't return any thing so there will be an error. */
 
-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
+/* As predicted the function does not return any thing. But the first call gives 320. and the second undefine. */
 
 // 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 +1,20 @@
 // Predict and explain first...
 //  =============> write your prediction here
+/* The code will give us the sum of 10 and 32 which will be " The sum of 10 and 32 is 42" */
 
-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
+/* the call of the function gives undefine result. the reason for this is the semicolon after return which shouldn't be placed there.
 // Finally, correct the code to fix the problem
-//  =============> write your new code here
+//  =============> 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

@@ -2,8 +2,12 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+/* I predict that the three call are giving 
+The last digit of 42 is 2
+The last digit of 105 is 5
+The last digit of 806 is 6    */
 
-const num = 103;
+/*const num = 103;
 
 function getLastDigit() {
   return num.toString().slice(-1);
@@ -12,13 +16,25 @@ 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
+/* because the num is determined at fires and 103 is given to the num. as a result we see the same result.*/
 // 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

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

@@ -14,6 +14,9 @@
 // Then when we call this function with the weight and height
 // It should return their Body Mass Index to 1 decimal place
 
-function calculateBMI(weight, height) {
+function calculateBMI(weight, height) { 
+    const bmi= weight/ (height*height)
+    return bmi.toFixed(1);
     // return the BMI of someone based off their weight and height
-}
+}
+console.log(calculateBMI(86,1.70));

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 toUpperCase(text) {
+    return text.toUpperCase();
+}
+
+console.log(toUpperCase("hello there"));
+console.log(toUpperCase("lord of the ring"));