Sheffield | ITP-Jan-26 | Hayriye Saricicek | Sprint 1 | Structuring and Testing Data

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

@@ -3,4 +3,5 @@ let count = 0;
 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
+// Line 3 increments the variable by 1
+

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

@@ -5,7 +5,10 @@ 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]}`;
+
+console.log(initials);
+
 
 // https://www.google.com/search?q=get+first+character+of+string+mdn
 

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

@@ -17,7 +17,7 @@ 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 ext =base.slice(base.lastIndexOf(".") + 1)
 
 // https://www.google.com/search?q=slice+mdn

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

@@ -7,3 +7,13 @@ 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
+
+console.log(num);
+
+//num is a random number between 1 and 100 including 1 and 100 [1,100]
+//Math.floor rounds the decimal number to nearest lower number
+// Math.random() generates a random decimal number between 0 and 1 including 0 but not including 1 [0,1)
+// when max – min need to add +1 or not all the numbers will be 
+// included for instance max=5 min=1 5-1=4 but there are 
+// 5 numbers, 1, 2, 3, 4,5 so need to +1
+//• + minimum → shift the range up to start at the minimum value

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

@@ -1,2 +1,3 @@
-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?
+//putting two forward slashes at the start of the line makes it a comment, which means the computer will ignore it when running the program

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;
+//const age = 33; needs to be let or the value cannot be reassigned
+let age = 33;
 age = age + 1;

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

@@ -1,5 +1,9 @@
 // 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}`);
+//console.log(`I was born in ${cityOfBirth}`);
+//const cityOfBirth = "Bolton";
+// these are in the wrong order.  Cannot access the value of cityOfBirth before it has been declared.  Need to declare the variable first and then log it to the console.
+
 const cityOfBirth = "Bolton";
+console.log(`I was born in ${cityOfBirth}`);

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

@@ -7,3 +7,16 @@ 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
+
+
+//cardNumber is a number and slice does not work with numbers only strings
+// to fix this we can convert the number to a string and then use slice 
+// to get the last 4 characters of the string, which will be the last 4 digits of the original number
+// const last4DigitsString = cardNumber.toString().slice(-4);
+// or make it into a function that takes a number as an argument and returns the last 4 digits as a string
+
+function last4Digits(cardNumber) {
+  return `${cardNumber}`.slice(-4);    
+}
+
+console.log(last4Digits(cardNumber)); 

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

@@ -1,2 +1,4 @@
 const 12HourClockTime = "20:53";
-const 24hourClockTime = "08:53";
+const 24hourClockTime = "08:53";
+// variable names cannot begin with a number
+// can change to clockTime12Hour and clockTime24Hour or something similar to make it valid

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

@@ -12,11 +12,25 @@ 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 4 function calls - Replace All is called twice and Number is called twice
+// if console.log is considered a function call then there are 5 function calls in total 
 
 // 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?
+// there is a comma missing in line 5 it should be 
+// priceAfterOneYear = Number(priceAfterOneYear.replaceAll(",", ""));
+// Replace All requires two arguments which should be separated by a comma, without the comma
+// it cannot tell where the first argument ends and the second argument begins
 
 // c) Identify all the lines that are variable reassignment statements
+// there are 2 variable reassignment statements
+// carPrice is reassigned on line 4 - the original value was declared in the let statement on line 1
+// priceAfterOneYear is reassigned on line 5 - the original value was declared in the let statement on line 2
 
 // d) Identify all the lines that are variable declarations
+// variable declarations are where the variable is declared for the first time
+// This happens in lines 1, 2 with let statements and in lines 7, 8 with const statements
 
 // e) Describe what the expression Number(carPrice.replaceAll(",","")) is doing - what is the purpose of this expression?
+// it replaces the commas in the numbers such as 20,000 so calculations can be done 
+// with commas the numbers are recognised as a string but with spaces they can be recognised as numbers
+// calculations cannot be performed on strings so they need to be converted to numbers 

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

@@ -1,4 +1,4 @@
-const movieLength = 8784; // length of movie in seconds
+const movieLength = 15560; // length of movie in seconds
 
 const remainingSeconds = movieLength % 60;
 const totalMinutes = (movieLength - remainingSeconds) / 60;
@@ -12,14 +12,27 @@ 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 declarations - remainingSeconds, totalMinutes, remainingMinutes, 
+// totalHours, result and movieLength
 
 // b) How many function calls are there?
+// there is 1 function call - console.log is called on the last line to print the result to the console
 
 // c) Using documentation, explain what the expression movieLength % 60 represents
 // https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Arithmetic_Operators
+// It is counting the remaining seconds after all the full minutes have been taken out of the movie length.
+// For example if the movie length is 125 seconds, then 125 % 60 would give us 5 seconds remaining after taking out the full minutes (2 minutes in this case).
 
 // d) Interpret line 4, what does the expression assigned to totalMinutes mean?
+// The expression (movieLength - remainingSeconds) / 60 calculates the total number of minutes in the movie length.
+// It subtracts the remaining seconds from the total seconds and then divides by 60 to get the total minutes.
 
 // e) What do you think the variable result represents? Can you think of a better name for this variable?
+// result gives the length of the movie in hours, minutes and seonds
+// a better name may be movieLengthFormatted or something similar
 
 // f) Try experimenting with different values of movieLength. Will this code work for all values of movieLength? Explain your answer
+// Yes, this code will work for all values of movieLength 
+//%60 gives the remainder and the remainder is always taken away before dividing for minutes and hours 
+// so it will always give the correct number of hours, minutes and seconds regardless of the length of 
+// the movie in seconds.

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

@@ -11,6 +11,7 @@ const pounds = paddedPenceNumberString.substring(
   paddedPenceNumberString.length - 2
 );
 
+
 const pence = paddedPenceNumberString
   .substring(paddedPenceNumberString.length - 2)
   .padEnd(2, "0");
@@ -25,3 +26,23 @@ 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): 
+// removes the last character "p" from the string to get just the number part of the price in pence
+
+//3. const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0"):
+// checks if the number is 3 digits and if it is less than 3 digits adds leading zeros to make it 3 digits long
+// if it is less than 3 digits long it adds leading zeros ie if 5p it would become 005
+
+//4. const pounds = paddedPenceNumberString.substring(0, paddedPenceNumberString.length - 2):
+// Ignores the last 2 numbers in the string (these are pence) and defines the remaining numbers as pounds.
+// So if the number was 399 that would be £3.  If th number was 2050 that would be £20
+// if it was 5p it would be 0
+
+//5. const pence = paddedPenceNumberString.substring(paddedPenceNumberString.length - 2).padEnd(2, "0"):
+// takes the last 2 numbers of the string which represent the pence and if it is less than 2 digits adds trailing zeros to make it 2 digits long
+// due to step 3 the string should always have at least 3 numbers but this is a safety precaution
+
+//6. console.log(`£${pounds}.${pence}`): prints the final result in the format of £pounds.pence to the console
+// prints the result £pounds.pence  so in this case £3.99  it prints the £ sign then the value of pounds 
+// designated by the $ sign and the value of pence designated by the $sign

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

@@ -11,8 +11,23 @@ In the Chrome console,
 invoke the function `alert` with an input string of `"Hello world!"`;
 
 What effect does calling the `alert` function have?
+A pop up box appears saying thecharitych.com says this is an alert, the function returns undefined.
 
 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?
+A pop up box appears saying thecharitych.com says What is your name
+with the options to complete name, press ok or press cancel
+
 What is the return value of `prompt`?
+
+Using:
+const myName = prompt("What is your name?");
+myName;
+
+If I click ok without entering my name the prompt goes off the screen and an empty string ("") is returned
+
+If I click cancel without entering my name the prompt goes off the screen and null is returned
+
+If I put my name Hayriye in and click ok then it goes off the screen and a string containing the users input 
+(in this case Hayriye) is returned

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

@@ -5,12 +5,31 @@ 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?
+ƒ log() { [native code] }
 
 Now enter just `console` in the Console, what output do you get back?
+console {debug: ƒ, error: ƒ, info: ƒ, log: ƒ, warn: ƒ, …}
 
 Try also entering `typeof console`
+'object'
 
 Answer the following questions:
 
 What does `console` store?
+console stores functions and allows you to display and inspect information in the browser console.
+
 What does the syntax `console.log` or `console.assert` mean? In particular, what does the `.` mean?
+console.log prints the value of whatever you ask it to print ie console.log(portfolio) would print the value of portfolio whereas console.log("portfolio") would print the actual word portfolio.
+
+console.assert tests for a condition but only returns a message if the condition is false.  For instance it may be used to check the age of a person to restrict access to a site for adults only.
+
+the full stop is used to separate an object from its method.  
+In console.log and console.assert console is the object and log and assert are methods.
+The full stop is called the 'dot operator' or 'member access operator'
+The dot operator accesses a property or method of an object 
+For example console.log means access the log method from the console object 
+and console.assert means access the assert method from the console object
+
+
+
+