London|ITP-September-2025|Alexandru Pocovnicu|Sprint 1 #806

alexandru-pocovnicu · 2025-10-30T11:38:36Z

Learners, PR Template

Self checklist

I have titled my PR with Region | Cohort | FirstName LastName | Sprint | Assignment Title
My changes meet the requirements of the task
I have tested my changes
My changes follow the style guide

Changelist

I implemented functions to satisfy pre-written test requirements

…median calculation logic

…prove null handling

…edundant code

…edian calculation logic

github-actions · 2025-10-30T11:38:52Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-10-30T11:38:53Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-10-30T11:38:55Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-10-30T11:38:57Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-10-30T11:38:58Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-10-30T11:39:03Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

cjyuan · 2025-11-08T15:11:16Z

Sprint-1/fix/median.js

+
+  const middleIndex = Math.floor(sortedList.length / 2);
+
+  const median = sortedList.slice(middleIndex)[0];


There is a more compact and more efficient way to access the element at position middleIndex.

cjyuan · 2025-11-08T15:13:09Z

Sprint-1/implement/dedupe.js

+    return [];
+  }
+  const arrCopy = arr.slice(0);
+  console.log(arrCopy);


Do you need this console.log() statement for the function to work?

cjyuan · 2025-11-08T15:14:47Z

Sprint-1/implement/dedupe.js

+  if (arr.length === 0) {
+    return [];
+  }
+  const arrCopy = arr.slice(0);


Line 7 will create a new array. We don't have to create another array here.

cjyuan · 2025-11-08T15:18:56Z

Sprint-1/implement/dedupe.test.js

+test("Given an array with no duplicates,return a copy of the original array", () => {
+  expect(dedupe([1, "y", 4, 7])).toEqual([1, "y", 4, 7]);
+});


The current test code cannot check if the returned array is a copy of the original array because toEqual() compares objects (including arrays) by value. To illustrate,

const A = [2, 3, 1]; const B = [...A]; // B is a copy of A // This set of code cannot distinguish if the compared objects are the same objects. expect(A).toEqual(A); // true expect(A).toEqual(B); // true

In order to check if the returned array is a copy of the original array, we would need additional checks.
Can you find out what code you need to add in order to ensure the returned value is not the original array?

cjyuan · 2025-11-08T15:40:22Z

Sprint-1/implement/max.js

+  if (elements.length === 0) {
+    return -Infinity;
+  } else if (elements.length === 1) {
+    return elements[0];
+  }
+  if (elements.every((element) => typeof element !== "number")) {
+    return NaN;
+  }
+  let filteredElements = elements.filter(
+    (element) => typeof element === "number"
+  );
+  let orderedElements = filteredElements.sort((a, b) => a - b);
+  return orderedElements[orderedElements.length - 1];


You could also consider treating an array that doesn’t contain any numbers as an empty array; both of them do not contain any numbers.

Does your function return the value you expect from the following function calls?

findMax([ "Foo" ]); findMax([ "Foo", "Bar" ]); findMax([ NaN, 1, 2, 3, NaN ]);

cjyuan · 2025-11-08T15:45:31Z

Sprint-1/implement/sum.js

+  if (elements.every((element) => typeof element !== "number")) {
+    return NaN;
+  }
+  const filteredElements = elements.filter(
+    (element) => typeof element === "number"
+  );


When an array contains at least one number, the code on lines 8-13 would end up processing the array elements twice.
Can you figure out a more efficient approach that only requires processing the array elements once?

cjyuan · 2025-11-08T15:46:08Z

Sprint-1/implement/sum.test.js

+test("Given an array with decimal/float numbers,return the correct total sum", () => {
+  expect(sum([-1.5, 1.5, 4.5])).toEqual(4.5);
+});


Decimal numbers in most programming languages (including JS) are internally represented in "floating point number" format. Floating point arithmetic is not exact. For example, the result of 46.5678 - 46 === 0.5678 is false because 46.5678 - 46 only yield a value that is very close to 0.5678. Even changing the order in which the program add/subtract numbers can yield different values.

So the following could happen

expect( 1.2 + 0.6 + 0.005 ).toEqual( 1.805 ); // This fail expect( 1.2 + 0.6 + 0.005 ).toEqual( 1.8049999999999997 ); // This pass expect( 0.005 + 0.6 + 1.2 ).toEqual( 1.8049999999999997 ); // This fail console.log(1.2 + 0.6 + 0.005 == 1.805); // false console.log(1.2 + 0.6 + 0.005 == 0.005 + 0.6 + 1.2); // false

Can you find a more appropriate way to test a value (that involves decimal number calculations) for equality?

Suggestion: Look up

Checking equality in floating point arithmetic in JavaScript

Checking equality in floating point arithmetic with Jest

cjyuan · 2025-11-08T15:50:48Z

Sprint-1/implement/sum.js

+  if (elements.length === 0) {
+    return 0;
+  }
+  if (elements.length === 1) {
+    return elements[0];
+  }


Why give special treatment to an array with one element?

github-actions · 2025-11-08T15:51:24Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

github-actions · 2025-11-08T15:51:24Z

Your PR's title isn't in the expected format.

Please check the expected title format, and update yours to match.

Reason: Wrong number of parts separated by |s

If this PR is not coursework, please add the NotCoursework label (and message on Slack in #cyf-curriculum or it will probably not be noticed).

alexandru-pocovnicu added 19 commits October 24, 2025 10:12

Add initial test file for mean calculations

71fa218

Add mean.js file for mean calculations

927769b

Remove mean.js and mean.test.js files

a393af9

Update dependencies in package-lock.json to latest versions

057a7dd

Refactor calculateMedian function to handle mixed values and improve …

bc5e43c

…median calculation logic

Add workspace configuration for project structure and Jest settings

b13a731

Refactor calculateMedian function to filter non-numeric values and im…

552eb4c

…prove null handling

Refactor calculateMedian function to improve null checks and remove r…

1e0393e

…edundant code

Refactor calculateMedian function to streamline sorting and improve m…

b78089c

…edian calculation logic

Add tests for findMax function to cover various input scenarios

4f6b45e

Refactor findMax function to enhance readability and maintainability

5d670ec

Implement tests for sum function to validate various input scenarios

879eb0e

Implement sum function to calculate the sum of an array of numbers

157b5f7

Implement tests for dedupe function to validate various input scenarios

c85cfda

Implement dedupe function to remove duplicate values from an array

5619c22

Format code for consistency and readability in dedupe function

abd3a43

Format dedupe tests for consistency and readability

ee2fd08

Fix spacing in comment for consistency in includes tests

584bd6f

Refactor includes function to use for...of loop for improved readability

908c81e

alexandru-pocovnicu added the Needs Review Trainee to add when requesting review. PRs without this label will not be reviewed. label Oct 30, 2025

cjyuan reviewed Nov 8, 2025

View reviewed changes

cjyuan added Reviewed Volunteer to add when completing a review with trainee action still to take. and removed Needs Review Trainee to add when requesting review. PRs without this label will not be reviewed. labels Nov 8, 2025


		const middleIndex = Math.floor(sortedList.length / 2);

		const median = sortedList.slice(middleIndex)[0];

Uh oh!

London|ITP-September-2025|Alexandru Pocovnicu|Sprint 1 #806

Are you sure you want to change the base?

London|ITP-September-2025|Alexandru Pocovnicu|Sprint 1 #806

Uh oh!

Conversation

alexandru-pocovnicu commented Oct 30, 2025 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Learners, PR Template

Changelist

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

github-actions bot commented Oct 30, 2025

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

github-actions bot commented Nov 8, 2025

Uh oh!

github-actions bot commented Nov 8, 2025

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants

alexandru-pocovnicu commented Oct 30, 2025 •

edited

Loading