NW6 | Fathi_Kahin | Module-JS1 | Week4

week-1/errors/0.js

@@ -1,2 +1,4 @@
-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?
+
+//answer. we comment the lines out like this

week-1/errors/1.js

@@ -2,3 +2,8 @@
 
 const age = 33;
 age = age + 1;
+// you cannot re-assign const instead we can use: let.
+
+//let age = 33;
+//age = age + 1;
+

week-1/errors/2.js

@@ -3,3 +3,8 @@
 
 console.log(`I was born in ${cityOfBirth}`);
 const cityOfBirth = "Bolton";
+
+// we should declare cityOfBirth before console.logging
+
+const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

week-1/errors/3.js

@@ -1,6 +1,11 @@
 const cardNumber = 4533787178994213;
 const last4Digits = cardNumber.slice(-4);
 
+//the card number must have a string format if we want to use the slice method
+
+const cardNumber = "4533787178994213";
+const last4Digits = cardNumber.slice(-4);
+
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
 // Make and explain a prediction about why the code won't work

week-1/errors/4.js

@@ -1,2 +1,7 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+// variables must start with letters
+
+const twelveHourClockTime = "20:53";
+const twentyFourhourClockTime = "08:53";
+

week-1/exercises/count.js

@@ -1,6 +1,11 @@
 let count = 0;
 
-count = count + 1;
+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
+
+count = count + 1; //line three is increasing 0 by 1 and the =  is the operator here.S
+
+
+

week-1/exercises/decimal.js

@@ -3,8 +3,16 @@ const num = 56.5467;
 
 // You should look up Math functions for this exercise https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Math
 
-// Create a variable called wholeNumberPart and assign to it an expression that evaluates to 56 ( the whole number part of num )
-// Create a variable called decimalPart and assign to it an expression that evaluates to 0.5467 ( the decimal part of num )
-// Create a variable called roundedNum and assign to it an expression that evaluates to 57 ( num rounded to the nearest whole number )
+// Create a variable called wholeNumberPart and assign the whole number part of num to it
+const wholeNumberPart = Math.floor(num);
+
+// Create a variable called decimalPart and assign the decimal part of num to it
+const decimalPart = num - wholeNumberPart;
+
+// Create a variable called roundedNum and assign num rounded to the nearest whole number to it
+const roundedNum = Math.round(num);
+
+console.log("Whole Number Part:", wholeNumberPart);
+console.log("Decimal Part:", decimalPart);
+console.log("Rounded Number:", roundedNum);
 
-// Log your variables to the console to check your answers

week-1/exercises/initials.js

@@ -4,3 +4,5 @@ let lastName = "Johnson";
 
 // Declare a variable called initials that stores the first character of each string in upper case to form the user's initials
 // Log the variable in each case
+
+let initials = (firstName[0] + middleName[0] + lastName[0]).toUpperCase();

week-1/exercises/paths.js

@@ -16,3 +16,34 @@ 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 filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
+
+// The index of the last slash 
+const lastSlashIndex = filePath.lastIndexOf("/");
+
+// The "base" part from the filePath
+const base = filePath.slice(lastSlashIndex + 1);
+
+// Logging the "base" part
+console.log(`The base part of ${filePath} is ${base}`);
+
+//.............................................................
+
+// Extracting the "dir" part from the filePath
+const dir = filePath.slice(0, lastSlashIndex);
+
+// The console-log
+console.log(`The dir part of ${filePath} is ${dir}`);
+//.............................................................
+
+// Extracting the "ext" part from the "base" part
+const extIndex = base.lastIndexOf(".");
+const ext = extIndex !== -1 ? base.slice(extIndex + 1) : "No extension";
+
+// the console log
+console.log(`The ext part of ${filePath} is ${ext}`);
+//......................................................
+
+

week-1/exercises/random.js

@@ -7,3 +7,8 @@ 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 several times to build an idea of what the program is doing
+
+//Answer
+
+// The variable -num- wil contain a random number between 1 and 100.
+

week-1/explore/chrome.md

@@ -10,9 +10,15 @@ Let's try an example.
 In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
+
 What effect does calling the `alert` function have?
+// was unable to do this. it only worked when I used console.log.
 
 Now try invoking the function `prompt` with a string input of `"What is your name?"` - store the return value of your call to `prompt` in an variable called `myName`.
 
+
 What effect does calling the `prompt` function have?
 What is the return value of `prompt`?
+..........................
+
+// I was only able to use console.log

week-1/explore/objects.md

@@ -5,12 +5,20 @@ In this activity, we'll explore some additional concepts that you'll encounter i
 Open the Chrome devtools Console, type in `console.log` and then hit enter
 
 What output do you get?
+`console.log`
 
 Now enter just `console` in the Console, what output do you get back?
+`console` 
 
 Try also entering `typeof console`
 
 Answer the following questions:
 
 What does `console` store?
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+
+The console.log() method prints a message to the web console. 
+
+The console.assert() method writes an error message to the console if the assertion is false. If the assertion is true, nothing happens.
+
+`.` means execute this”. 

week-1/interpret/percentage-change.js

@@ -12,9 +12,13 @@ console.log(`The percentage change is ${percentageChange}`);
 // Read the code and then answer the questions below
 
 // a) How many function calls are there in this file? Write down all the lines where a function call is made
+// ...........there are 2 function calls: 1) carPrice.replaceAll and 2) priceAfterOneYear.replaceAll
 
 // b) Identify all the lines that are variable reassignment statements
+//.......1) carPrice = Number(carPrice.replaceAll(",", ""));  and 2)  priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
 
 // c) Identify all the lines that are variable declarations
+//.....1. `let carPrice = "10,000";`    2. `let priceAfterOneYear = "8,543";`    3. `const priceDifference = carPrice - priceAfterOneYear;`   4. `const percentageChange = (priceDifference / carPrice) * 100;`
 
 // d) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//..... it is replacing all the comas in the string so that we can have numbers that we can calculate.

week-1/interpret/time-format.js

@@ -13,17 +13,19 @@ 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?
+// a) How many variable declarations are there in this program?  There are five variable declarations in this program:
 
-// b) How many function calls are there?
+// b) How many function calls are there? There are zero function calls 
 
-// c) Using documentation on MDN, explain what the expression movieLength % 60 represents
+// c) Using documentation on MDN, explain what the expression movieLength % 60 represents. it represents the reminder. 
+//                                    (It calculates the remaining seconds after all the full minutes have been counted.)
 
-// d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// d) Interpret line 4, what does the expression assigned to totalMinutes mean? It extracts the seconds in the movie length.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// the variable result represent (hours:minutes:seconds) time format, a better name would be (formattedTime)
 
 // f) Think about whether this program will work for all values of movieLength.
 //    Think of what values may cause problems for the code.
 //    Decide the result should be for those values, then test it out.
-//    Can you find any values of movieLength which don't give you what you'd expect?
+//    Can you find any values of movieLength which don't give you what you'd expect? yes, it is not considering (days) in the calculation.

week-1/interpret/to-pounds.js

@@ -27,3 +27,18 @@ 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 line  creates a new string variable
+//                                                  which represents the price in pence without the 'p' character.
+// 3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); 
+//                                                 : This line creates a new string variable with the value "399," 
+// 4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);
+//                                                 : This line takes the first character of the `paddedPenceNumberString`, 
+//                                                  which represents the pounds.
+// 5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"); 
+//                                         : This line extracts the pence part of the `paddedPenceNumberString`
+// 6. console.log(`£${pounds}.${pence}`);
+//                 : This line  combines the `pounds` and `pence` variables with the '£' symbol to to make it easy to read.
+
+
+

week-2/debug/0.js

@@ -5,3 +5,14 @@ function multiply(a, b) {
 }
 
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+localStorage
+
+// the result is showing 320, which is not  fully correct due to the term LocalStorage.
+// it should be written as below:
+
+function multiply(a, b) {
+  return a * b;
+}
+
+console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+

week-2/debug/1.js

@@ -1,8 +1,17 @@
 // Predict and explain first...
 
 function sum(a, b) {
-  return;
-  a + b;
+ return;
+ a + b }
+
+//console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+
+// the semi colon in the return statement will stop the function execution. it should be as follows:
+
+function sum(a, b) {
+  return a + b;
 }
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
+
+

week-2/debug/2.js

@@ -1,14 +1,25 @@
 // Predict and explain first...
 
-const num = 103;
+// const num = 103;
 
 function getLastDigit() {
-  return num.toString().slice(-1);
-}
+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
+//...........................................................................
+// first the (num) is not defined, second the (const num = 103;) is a fixed number and that is what it will 
+//          calculate for all numbers, their  last digit will remain 3, we can fix this by using
+//          the  following code:
+
+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

week-2/errors/0.js

@@ -4,6 +4,24 @@
 // interpret the error message and figure out why it's happening, if your prediction was wrong
 
 function capitalise(str) {
-  let str = `${str[0].toUpperCase()}${str.slice(1)}`;
-  return str;
+ let str = `${str[0].toUpperCase()}${str.slice(1)}`;
+ return str;
 }
+
+//....................................
+// the problem is that  (str) is already the input to the function
+
+function capitalise(str) {
+  let capitalizedStr = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return capitalizedStr;
+}
+
+const originalString = "i love cyf"; 
+const capitalizedString = capitalise(originalString);
+
+console.log(`Original: ${originalString}`);
+console.log(`Capitalized: ${capitalizedString}`);
+
+
+
+

week-2/errors/1.js

@@ -9,5 +9,36 @@ function convertToPercentage(decimalNumber) {
 
   return percentage;
 }
+//.................................
+
+// ANSWER.
+// We want the computer to perform a task: take the (decimalNumber ),, multiply it by 100, and add a '%' sign. 
+// However, we made a mistake by telling the computer "Hey computer, our special number is 'decimalNumber,' and by the way, it's 0.5!" 
+// This  will confuse the computer and will  result an error. To fix this, we need to correct our instructions, 
+// making sure that we only tell the computer about the (decimalNumber ) just once. If we solve this mistake, 
+// the computer will be able to carried out the task, (this is really a good example of how important is to give clear instructions, 
+//   and how important is to avoid repetition in computer programming).
+
+//Playing computer results:
+
+//  const decimalNumber is declared in the local scope
+// const decimalNumber = 0.5;
+//   A syntax error occurs here because you're trying to redeclare 'decimalNumber' in the same scope.
+
+//   const percentage = `${decimalNumber * 100}%`;
+//  This will not be reached due to the syntax error.
+
+// then we Called the function
+// convertToPercentage();
+// This also results in a syntax error because we are trying to redeclare 'decimalNumber' in the same scope.
+
+function convertToPercentage() {
+  const decimalNumber = 0.5;
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+
+console.log(convertToPercentage());
 
-console.log(decimalNumber);

week-2/errors/2.js

@@ -3,8 +3,19 @@
 // this function should square any number but instead we're going to get an error
 // what is happening? How can we fix it?
 
-function square(3) {
-    return num * num;
-}
+// function square(3) {
+//     return num * num;
+//    }
+
+//...........................................
+
+//ANSWER
 
 
+function square(num) {
+    return num * num;
+  }
+
+console.log(square(4)); 
+console.log(square(7)); 
+