Glasgow | ITP May -25 | Pandi Simatupang | Module-Structuring-and-Testing-Data | coursework/sprint-1

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
+
+console.log(`value of count is ${count}`)
+
+// what line 3 doing is add 1 to current value of "count" and saving or assigning the new value (which is 1) as new value

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

@@ -9,3 +9,9 @@ let initials = ``;
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 
+function getInitial(firstName, middleName, lastName) {
+  return firstName[0] + middleName[0] + lastName[0];
+}
+
+initials = getInitial("Creola", "Katherine", "Johnson");
+console.log(`initials is ${initials}`);

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

@@ -17,7 +17,11 @@ 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(1, lastSlashIndex);
+console.log(dir);
 
-// https://www.google.com/search?q=slice+mdn
+const dotIndex = base.lastIndexOf(".");
+const ext = base.slice(dotIndex + 1);
+console.log(ext);
+
+// https://www.google.com/search?q=slice+mdn

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

@@ -5,5 +5,11 @@ const num = Math.floor(Math.random() * (maximum - minimum + 1)) + minimum;
 
 // 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
+
+//Math.random() -> generates zero base random number
+// we need to multiply with digit number needed to allow possible number generated
+//Math.floor() method will round up to the base integer generated
+
 // 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
+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 +1,9 @@
 // trying to create an age variable and then reassign the value by 1
 
-const age = 33;
+//create variable age
+let age = 33;
+
+//reassign variable age by 1 (+1)
 age = age + 1;
+
+console.assert(age); //Oh no.. that is mr. const

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

@@ -1,5 +1,8 @@
 // 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}`);
+
+//it's not working because variable cityOfBirth was not defined.
+//change the position of -- const cityOfBirth = "Bolton"; -- before the logging will fix the problem

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

@@ -1,9 +1,13 @@
 const cardNumber = 4533787178994213;
-const last4Digits = cardNumber.slice(-4);
+const cardNumberStr = cardNumber.toString();
+const last4Digits = cardNumberStr.slice(-4);
 
 // 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
 // Then run the code and see what error it gives.
+console.log(last4Digits);
 // Consider: Why does it give this error? Is this what I predicted? If not, what's different?
+//can not slice a number, the given card number is integer NOT a List or array
 // Then try updating the expression last4Digits is assigned to, in order to get the correct value
+//fix by give double quotes to turn the number to sting or make a new variable assign cardNumber.toString()

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

@@ -1,2 +1,5 @@
-const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const ClockTime_12Hour = "20:53";
+const ClockTime_24hour = "08:53";
+
+//variable name convention issues...
+//variable name should not started a number

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 +12,13 @@ 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
-
+//------->ans: build-in function call line numbers 4,5 and 10
 // 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?
-
+//------->ans: error at line 5.
+//------->ans: add a missing comma
 // c) Identify all the lines that are variable reassignment statements
-
+//------->ans: line 4 (carPrice) and line 5 (priceAfterOneYear)
 // d) Identify all the lines that are variable declarations
-
+//------->and: line 1 and 2
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+//------->and: replace character comma with nothing or in other words remove it or delete it

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

@@ -1,4 +1,4 @@
-const movieLength = 8784; // length of movie in seconds
+const movieLength = 86401; // length of movie in seconds
 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
@@ -12,14 +12,15 @@ 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?
-
+//------->ans: 6
 // b) How many function calls are there?
-
+//------->ans: 1 at the last line, that is console.log() .. it is a built-in function.
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
-
+//------->ans: The remainder (%) operator returns the remainder left over when one operand is divided by a second operand. It always takes the sign of the dividend.
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
-
+//------->ans: (movieLength - remainingSeconds) / 60;
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
-
+//------->ans: it generates a number in "seconds", for selection of name? the selected one is fine. as long as it follows the variable names convention and the reader or debugger easily understand it.
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+//------->ans: it has a constrain or maybe limitation, that is if value movie length is bigger that 86400 the time shown not appropriate, it should give a hint that it more than a day

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

@@ -1,19 +1,24 @@
-const penceString = "399p";
+const penceString = "9p"; //init variable
 
 const penceStringWithoutTrailingP = penceString.substring(
   0,
   penceString.length - 1
-);
+); //remove p character at the end of the variable
+console.log(penceStringWithoutTrailingP);
+
+const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"); //
+console.log(paddedPenceNumberString); //give format of 3 zeroes if the number is less than 3 digits.
 
-const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
 const pounds = paddedPenceNumberString.substring(
   0,
   paddedPenceNumberString.length - 2
-);
+); //get ponds value conversion changes for given pence
+
+console.log(pounds);
 
 const pence = paddedPenceNumberString
   .substring(paddedPenceNumberString.length - 2)
-  .padEnd(2, "0");
+  .padEnd(2, "0"); //get the reminds after conversion to pounds
 
 console.log(`£${pounds}.${pence}`);
 

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

@@ -1,6 +1,6 @@
 Open a new window in Chrome,
 
-then locate the **Console** tab.
+then locate the **Console** tab. (short cut for linux ctrl+shift+j)
 
 Voila! You now have access to the [Chrome V8 Engine](https://www.cloudflare.com/en-gb/learning/serverless/glossary/what-is-chrome-v8/).
 Just like the Node REPL, you can input JavaScript code into the Console tab and the V8 engine will execute it.
@@ -9,10 +9,16 @@ Let's try an example.
 
 In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
+ans: done!
 
 What effect does calling the `alert` function have?
+ans: pops out a message with given strings inside alert arguments
 
 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`.
+ans: myname = prompt("What is your name?");
 
 What effect does calling the `prompt` function have?
+ans: pops out a message with input field and we can store the input value into a variable
+
 What is the return value of `prompt`?
+ans: return value is the string given by user

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

@@ -3,14 +3,17 @@
 In this activity, we'll explore some additional concepts that you'll encounter in more depth later on in the course.
 
 Open the Chrome devtools Console, type in `console.log` and then hit enter
+ans: done!
 
 What output do you get?
-
+ans: undefined
 Now enter just `console` in the Console, what output do you get back?
-
+ans: a list of available methods for console.
 Try also entering `typeof console`
-
+ans: done!
 Answer the following questions:
-
+ans: object
 What does `console` store?
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+ans: console.log() will print given parameter in it,
+console.assert(<expression>, <comments>) only print out the given comment if expression inside it is fault or false

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

@@ -6,7 +6,7 @@
 // =============> write your prediction of the error here
 
 function square(3) {
-    return num * num;
+  return num * num;
 }
 
 // =============> write the error message here
@@ -15,6 +15,4 @@ function square(3) {
 
 // Finally, correct the code to fix the problem
 
-// =============> write your new code here
-
-
+// =============> write your new code here

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

@@ -15,5 +15,5 @@
 // It should return their Body Mass Index to 1 decimal place
 
 function calculateBMI(weight, height) {
-    // return the BMI of someone based off their weight and height
-}
+  // return the BMI of someone based off their weight and height
+}