London | 25-ITP-Sep| Sophia Mohamed | Sprint 1 | coursework/sprint-1

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

@@ -4,3 +4,4 @@ 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
+//In line 3 we are taking the current value of count (which is 0) and adding 1 to it, and store the new value back into  count" so now count is 1.the = is an assignment operator that Assigns values to variables so it takes the value on the right side (count + 1) and assigns it to the variable on the left side (count). 

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

@@ -5,7 +5,9 @@ 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
 
+console.log(initials); //that should print "CKJ"
+//so the code is going to check the first character of each variable that means “the character at position 0

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

@@ -17,7 +17,12 @@ 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);// the slice is a method that cuts out part of a string and returns it as a new string. we use it here to get the dir part of the filePath
+const ext = base.slice(base.lastIndexOf("."));//the ext is any thing after the last dot 
+//const filePath = "/Users/mitch/cyf/Module-JS1/week-1/interpret/file.txt";
+//const dir = "/Users/mitch/cyf/Module-JS1/week-1/interpret";
+
+console.log(`The dir part of ${filePath} is ${dir}`);
+console.log(`The ext part of ${filePath} is ${ext}`);   
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -2,8 +2,53 @@ const minimum = 1;
 const maximum = 100;
 
 const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
+console.log(num);
 
 // In this exercise, you will need to work out what num represents?
 // 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
+
+//num is a random number between minimum and maximum (inclusive)
+/*Math.random()
+
+This gives you a random decimal number between 0 (inclusive) and 1 (exclusive) — meaning it can be 0, but never exactly 1.
+
+Example outputs:
+0.23 
+
+/*(maximum - minimum + 1)
+
+This calculates how many whole numbers are in the range, including both ends.
+
+Example:
+100 - 1 + 1 = 100
+
+So, there are 100 possible integers from 1 to 100.
+
+/*Math.random() * (maximum - minimum + 1)
+
+This scales the random decimal to the desired range size.
+
+Example if Math.random() gave 0.57:
+0.57 * 100 = 57
+/*Math.floor(...)
+The Math.floor() method in JavaScript is used to round a number down to the nearest integer, regardless of whether the number is positive or negative or has a decimal part.
+Example:
+Math.floor(57.8) → 57
+
+/*+ minimum
+
+Finally, we shift the range up so it starts at 1 instead of 0.
+0–99 becomes 1–100*/
+
+//The order for evaluation is:
+/*maximum - minimum + 1
+
+Math.random() * (that result)
+
+Math.floor(...)
+
++ minimum*/
+
+//I run the code several times and got different numbers one was 60 the other one was 88

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

@@ -1,2 +1,6 @@
-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?
+
+
+//if we have any instructions or explanations in our code without the computer executing them,we can use comments
+//comments In javascript are created by using (//) for single line comments

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

@@ -2,3 +2,7 @@
 
 const age = 33;
 age = age + 1;
+// This will give an error because we only use const for Fixed values so we can change const to let
+let age = 33;
+age = age + 1;
+console.log(age); // that should print 34

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}`);
+ //we have to declare the variable cityOfBirth with const or let before using it in the console.log statement

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

@@ -1,9 +1,18 @@
 const cardNumber = 4533787178994213;
 const last4Digits = cardNumber.slice(-4);
-
+console.log(last4Digits);
 // The last4Digits variable should store the last 4 digits of cardNumber
 // However, the code isn't working
 // Before running the code, make and explain a prediction about why the code won't work
+//the slice method is used for strings not numbers.
 // Then run the code and see what error it gives.
+//Uncaught TypeError: cardNumber.slice is not a function
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
+//javascript can not slice a number 
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+//I have added the console.log to see the output.
+//there is another way to get the last 4 digits by using slice method is to convert the number to a string first by using toString() method
+const last4Digits = cardNumber.toString().slice(-4); //it wil print "4213"
+//If you want it to be a number, you can convert it back:
+const last4Digits = Number(cardNumber.toString().slice(-4));
+Now last4Digits will be 4213 as a number.

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

@@ -1,2 +1,10 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+
+//because variables names cannot start with a number
+//I have changed the variable names to start with a letter
+const twelveHourClockTime = "08:53 PM";
+const twentyFourHourClockTime = "20:53";
+console.log(twelveHourClockTime);
+console.log(twentyFourHourClockTime); 
+// that should print "08:53 PM" and "20:53"

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

@@ -2,7 +2,7 @@ let carPrice = "10,000";
 let priceAfterOneYear = "8,543";
 
 carPrice = Number(carPrice.replaceAll(",", ""));
-priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll("," ,""));
 
 const priceDifference = carPrice - priceAfterOneYear;
 const percentageChange = (priceDifference / carPrice) * 100;
@@ -12,11 +12,26 @@ 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
-
+//after running the code I found 5 function calls
+//line 1: replaceAll
+//line 2: replaceAll
+//line 4: Number
+//line 5: Number
+//line 8: console.log
 // 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?
+// after running the code i found an error in line 5 missing a comma in the replaceAll method to fix it I have added the comma
 
 // c) Identify all the lines that are variable reassignment statements
+carPrice = Number(carPrice.replaceAll(",", ""));
+priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+
 
 // d) Identify all the lines that are variable declarations
+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?
+// Fist the car price is a string so we can't do any calculation on it yet 
+//so first we remove all the comma by using replaceAll method then we convert it to a number by using Number method

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

@@ -12,14 +12,20 @@ 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 is 6 variable declarations 
 
 // b) How many function calls are there?
+// there is only 1 function call which is the last onw in line 10 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
+//modulus operator % gives the remainder after dividing one number by another.which is in this case8784 % 60 = 24 second 
+
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+//we are converting the seconds into minutes by dividing by 60 
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
-
+//Duration of the movie in hours, minutes, and seconds.
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+//yes it will work for all values of movieLength  because the code will always convert seconds into hours, minutes, and seconds format.

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

@@ -24,4 +24,9 @@ console.log(`£${pounds}.${pence}`);
 // Try and describe the purpose / rationale behind each step
 
 // To begin, we can start with
-// 1. const penceString = "399p": initialises a string variable with the value "399p"
+// 1. const penceString = "399p":  a string variable with the value "399p"
+//2.in line 3 because the value is a string we can't do any calculation on it yet we need to convert it to a number so the first step is to get rid of the letter P at the end so no matter how long the number is we get rid of the last character.
+//3. in line 8 we make sure the number has 3 digits so if needed we add zeros at the start at the number
+//4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2);: by taking away the last 2 digit we will get the pounds in this example the amount is 399 so by taking away the 99 we will get 3 pounds 
+//6. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0");: the same thing again now extracts the pence part by taking the last two digits if it is one digit we add 0 at the end to make it two digits
+// in line 18 to print the result in the right format £ sign then pounds then a dot and then pence

Sprint-1/4-stretch-explore/chrome.md

@@ -11,8 +11,14 @@ In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
 What effect does calling the `alert` function have?
+the browser shows a popup message box with your text — "Hello world!"
 
 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`.
 
+let myName = prompt("What is your name?");
+The browser shows a popup with a text input box and OK / Cancel buttons.
+
 What effect does calling the `prompt` function have?
+It display a dialog box that prompts the user for input
 What is the return value of `prompt`?
+The text the user entered (string) if clicked OK, or null if Cancel

Sprint-1/4-stretch-explore/objects.md

@@ -5,12 +5,17 @@ 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?
+nothing 
 
 Now enter just `console` in the Console, what output do you get back?
+error message 
 
 Try also entering `typeof console`
 
 Answer the following questions:
 
 What does `console` store?
+console store Functions
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+console.log  will print the message to the console
+console.assert will print a message if the condition is false