London | 26-ITP_May | Vito Moratti | Sprint 2 | Coursework/sprint 2

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

@@ -1,7 +1,9 @@
 // Predict and explain first...
 //  =============> write your prediction here
-
-// call the function capitalise with a string input
+// Well, I think the variable "str" is being declared twice, so the code will
+//  through an error message.
+//
+//call the function capitalise with a string input
 // interpret the error message and figure out why an error is occurring
 
 function capitalise(str) {
@@ -10,4 +12,12 @@ function capitalise(str) {
 }
 
 // =============> write your explanation here
+//The variable "str" has been used as a parameter for the capitalise function
+//and also been declared again inside the function. I think if "let" is removed
+//the code will work.
 // =============> write your new code here
+function capitalise(str) {
+  str = `${str[0].toUpperCase()}${str.slice(1)}`;
+  return str;
+}
+console.log(capitalise("sorted"));

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

@@ -1,20 +1,40 @@
 // Predict and explain first...
-
 // Why will an error occur when this program runs?
 // =============> write your prediction here
-
+// I think there will be an error as "decimalNumber" variable has already been declared as a parameter in
+// "convertToPercentage" function
+// 
 // 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
+// =============Explanation ===============
+// the "decimalNumber" variable is a local variable and can only be seen inside "convertToPercentage" function
+// therefore when called outside the function it triggers "ReferenceError"
 
 // Finally, correct the code to fix the problem
+// =========correction=========
+// problem can be fixed by moving the variable declaration outside the function
+//  and making it global
+
 // =============> write your new code here
+
+const decimalNumber = 0.5;
+function convertToPercentage(decimalNumber) {
+  const percentage = `${decimalNumber * 100}%`;
+
+  return percentage;
+}
+
+console.log(decimalNumber);
+console.log(convertToPercentage(decimalNumber));
+
+

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

@@ -1,20 +1,24 @@
-
 // Predict and explain first BEFORE you run any code...
 
 // this function should square any number but instead we're going to get an error
 
 // =============> write your prediction of the error here
-
-function square(3) {
+//=========Prediction=============
+// I think there will not be en error till we call the function.
+/*function square(num) {
     return num * num;
 }
-
+console.log(square(5))*/
 // =============> write the error message here
-
+// Unexpected number
 // =============> explain this error message here
-
+// I think it function expects parameter as a variable rather than  a number.
 // Finally, correct the code to fix the problem
-
+// ===========correction=========
+// to correct the code we need to introduce parameter as a variable, rather than a number.
+// that way any number can be passed when function is called.
 // =============> write your new code here
-
-
+function square(num) {
+  return num * num;
+}
+console.log(square(5));

Sprint-2/2-mandatory-debug/0.js

@@ -1,14 +1,25 @@
 // Predict and explain first...
 
 // =============> write your prediction here
-
-function multiply(a, b) {
+//===========Prediction=======
+// I think the code will not produce the desired result as the function is not returning any value
+/*function multiply(a, b) {
   console.log(a * b);
 }
-
 console.log(`The result of multiplying 10 and 32 is ${multiply(10, 32)}`);
+console.log(multiply(3, 5));
+typeof(multiply(3, 4));*/
 
 // =============> write your explanation here
-
+//===============Explanation=========
+// The function itself prints out the result, but the result has no (type) as such and can not be used as
+// a data type. 
+//
 // Finally, correct the code to fix the problem
+//============correction============
+// To correct the code "return" needs to be introduced.
 //  =============> 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 +1,23 @@
 // Predict and explain first...
 //  =============> write your prediction here
-
+// =============explanation==========
+// I think will either give error, or no result at all as there is  a ";" semicolon after
+//  the return statement and the actual calculation is not assigned to anything.
 function sum(a, b) {
   return;
-  a + b;
+   a + b;
 }
 
 console.log(`The sum of 10 and 32 is ${sum(10, 32)}`);
 
 // =============> write your explanation here
+//==============Explanation===============
+//To fix the code the ";" must be removed, and the calculation 
+//needs to be placed next to the "return"
 // Finally, correct the code to fix the problem
 //  =============> 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

@@ -2,6 +2,9 @@
 
 // Predict the output of the following code:
 // =============> Write your prediction here
+//============Prediction========
+// I think the code output will be  "3" in al three cases as "num variable is declared outside the function and 
+// not used as a parameter for the function"
 
 const num = 103;
 
@@ -14,11 +17,30 @@ 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
+// prediction matched
 // =============> 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
+//===============Explanation===========
+// The variable is not used as a parameter of the function, and therefore
+//  is ignored when passed inside function call.
 // Finally, correct the code to fix the problem
+//
 // =============> write your new code here
+//const num = 103;
 
+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
+// =============explanation==================
+// The variable is not used as a parameter of the function, and therefore
+//  is ignored when passed inside function call.

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

@@ -13,7 +13,10 @@
 // Given someone's weight in kg and height in metres
 // 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) {
-    // return the BMI of someone based off their weight and height
-}
+    let bmi = weight / (height **2 )// weight divided by height squared.
+    return  bmi.toFixed(1)// toFixed(1) insures that result is displayed with 1 decimal place
+}                                                           
+//
+console.log(calculateBMI(87, 1.86))

Sprint-2/3-mandatory-implement/2-cases.js

@@ -14,3 +14,11 @@
 // 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 upper_snake_case(word) {
+    let new_word = word.toUpperCase();// capitalises string
+    let split_word = new_word.split(" ");// turns string into array in order to to use "join()" method
+    let joined_word = split_word.join("_")// joins strings with "_" to make it UPPER_SNAKE
+    return joined_word; 
+}
+console.log(upper_snake_case("hello there"));

Sprint-2/3-mandatory-implement/3-to-pounds.js

@@ -4,3 +4,37 @@
 // You will need to declare a function called toPounds with an appropriately named parameter.
 
 // You should call this function a number of times to check it works for different inputs
+function toPounds(penceString) {
+  const penceStringWithoutTrailingP = penceString.substring(
+    0,
+    penceString.length - 1
+  ); //variable
+  //  "penceStringWithoutTrailingP" declared and assigned first three characters
+  //  of "penceString" using the substring method, removing the trailing "p".
+
+  const paddedPenceNumberString = penceStringWithoutTrailingP.padStart(3, "0");
+  // variable "paddedPenceNumberString" declared and assigned the value of "penceStringWithoutTrailingP"
+  // padded to a minimum length of 3 characters with leading zeros using the padStart method. Which is clever way,
+  // really to replace it with zeros if number of pence is less than 3 characters long.
+
+  const pounds = paddedPenceNumberString.substring(
+    0,
+    paddedPenceNumberString.length - 2
+  );
+  //Variable "pounds" declared and assigned value of "paddedPenceNumberString" but without the last
+  // two characters.
+
+  const pence = paddedPenceNumberString
+    .substring(paddedPenceNumberString.length - 2)
+    .padEnd(2, "0");
+  // Variable "pence" declared and assigned value of the last two characters of "paddedPenceNumberString"
+  // and padded to a minimum length of 2 characters with zeros at the end, padEnd method is used once again.
+  // it is to ensure that if the number of pence is less than 2 characters long, it will be padded with zeros
+  // at the end.
+
+  return `£${pounds}.${pence}`;
+  // Finally equivalent in "pounds" and "pence" is returned
+}
+console.log(toPounds("2345")); // testing with normal string of numbers
+console.log(toPounds("-2345")); // testing with string of negative numbers
+console.log(toPounds("0")); // testing with zero

Sprint-2/4-mandatory-interpret/time-format.js

@@ -14,6 +14,7 @@ function formatTimeDisplay(seconds) {
 
   return `${pad(totalHours)}:${pad(remainingMinutes)}:${pad(remainingSeconds)}`;
 }
+console.log(formatTimeDisplay(61))
 
 // You will need to play computer with this example - use the Python Visualiser https://pythontutor.com/visualize.html#mode=edit
 // to help you answer these questions
@@ -22,17 +23,26 @@ function formatTimeDisplay(seconds) {
 
 // a) When formatTimeDisplay is called how many times will pad be called?
 // =============> write your answer here
+// Answer to a) : when "formatTimeDisplay" is called "pad" is called 3 times
 
 // Call formatTimeDisplay with an input of 61, now answer the following:
 
 // b) What is the value assigned to num when pad is called for the first time?
 // =============> write your answer here
+// Answer to b) : value assigned to num when pad is called for the first time is 0 - zero
 
 // c) What is the return value of pad is called for the first time?
 // =============> write your answer here
+// Answer to c) : the return value on pad is the "numString" variable, which is string "00"
 
 // d) What is the value assigned to num when pad is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+// Answer to d) : Value assigned to "num" the last time "pad" is called is 1, one.
+// "num" in this case is a variable "remainingSeconds", which is a remainder of "seconds" (61)
+//  variable divided by 60, which is 1.
 
 // e) What is the return value of pad when it is called for the last time in this program?  Explain your answer
 // =============> write your answer here
+// Answer to e) : The return value of "pad" the last time pad called is the variable "numString"
+// which is - string "01". "toString" variable is a "num" converted to a string earlier in the function 
+// and makes it double digit string.

Sprint-2/5-stretch-extend/format-time.js

@@ -1,25 +1,72 @@
 // This is the latest solution to the problem from the prep.
 // Make sure to do the prep before you do the coursework
-// Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any bugs you find.
+// Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any
+// bugs you find.
+
+// This is the latest solution to the problem from the prep.
+// Make sure to do the prep before you do the coursework
+// Your task is to write tests for as many different groups of input data or edge cases as you can, and fix any
+// bugs you find.
 
 function formatAs12HourClock(time) {
-  const hours = Number(time.slice(0, 2));
-  if (hours > 12) {
-    return `${hours - 12}:00 pm`;
-  }
-  return `${time} am`;
+    const hours = Number(time.slice(0, 2)); // "hours" variable represents first two digits of the time string turned into number
+    const minutes = Number(time.slice(-2));// "mninutes" variable represents last two digits of the "time" string converted to number
+    if (hours === 12) {
+        return `${time}pm` // if time is "12:00" it will show 
+        //12:00 pm
+    } else if (hours === 24 && time.slice(-2) === "00") {
+        return `00:00am`;
+    } else if (hours === 24 && minutes > 0) {
+        return `00:${minutes}am`
+
+    }else if (hours > 12) {
+        return `${hours - 12}:${minutes}pm`;
+    }
+  return `${time}am`;
 }
-
 const currentOutput = formatAs12HourClock("08:00");
-const targetOutput = "08:00 am";
+const targetOutput = "08:00am";
 console.assert(
   currentOutput === targetOutput,
   `current output: ${currentOutput}, target output: ${targetOutput}`
 );
 
-const currentOutput2 = formatAs12HourClock("23:00");
-const targetOutput2 = "11:00 pm";
+const currentOutput2 = formatAs12HourClock("23:35");
+const targetOutput2 = "11:35pm";
 console.assert(
   currentOutput2 === targetOutput2,
-  `current output: ${currentOutput2}, target output: ${targetOutput2}`
+  `current output2: ${currentOutput2}, target output2: ${targetOutput2}`
 );
+const currentOutput3 = formatAs12HourClock("00:00");// 
+const targetOutput3 = "00:00am";// expecting new test to return "00:00 am"
+console.assert(
+  currentOutput3 === targetOutput3, 
+  `current output3: ${currentOutput3}, target output3: ${targetOutput3}`
+); // if currentOutput3 and targetOutput3 do not match, the assertion message will be given.
+
+const currentOutput4 = formatAs12HourClock("12:00");//
+const targetOutput4 = "12:00pm"; // expected output for "12:00" is "12:00 pm"
+console.assert(
+  currentOutput4 === targetOutput4,
+  `current output4: ${currentOutput4}, target output4: ${targetOutput4}`
+);// if currentOutput and targetOutput do not match, the assertion message will be given.
+const currentOutput5 = formatAs12HourClock("24:00");
+const targetOutput5 = "00:00am";
+console.assert(
+    currentOutput5 === targetOutput5,
+    `current output5: ${currentOutput5}, target output5: ${targetOutput5}`
+  ); // if 24:00 is entered and the output is not "00:00 am" the assertion message will be given
+
+// below is test to try with minutes
+const currentOutput6 = formatAs12HourClock("22:55");
+const targetOutput6 = "10:55pm";
+console.assert(currentOutput6 === targetOutput6, `current outpu6: ${currentOutput6}, target output6: ${targetOutput6}`);
+
+// following test tests what happens if time passed 24:00 hours.
+const currentOutput7 = formatAs12HourClock("24:25");
+const targetOutput7 = "00:25am";
+console.assert(currentOutput7 === targetOutput7, `current output7: ${currentOutput7}, target output: ${targetOutput7}`)
+
+
+
+