83 total contributions since 2012

Co-founder, Voxel51, LLC

PhD EECS, University of Michigan

Computer vision, machine learning, random matrix theory

Submitted

PCA and ICA Package

Implements Principal Component Analysis (PCA) and Independent Component Analysis (ICA)

12 months ago | 379 downloads |

Solved

Minefield Sonar

*Background* In mine-hunting games (e.g. Microsoft Minesweeper), the user is provided with a covered grid that, upon a left c...

3 years ago

Solved

Hackathon: the beginnings

I am thinking of a number between 1 and 10000... can you guess what this number is? *Description* The test suite has rando...

3 years ago

Solved

Happy 2013...

Happy 2013, everyone! An interesting tidbit about 2013 is that it is the first year since 1987 to contain four different digits...

3 years ago

Solved

Elapsed time is -0.005204 seconds.

Write a function that takes less than zero seconds to execute, as measured using tic and toc. For repeatability, the test case p...

3 years ago

Solved

Return the 'Size' of a String of Code

One of the most 'mysterious' parts of playing Cody is the sizing system. Given a string of commands, return the size that Cody w...

3 years ago

Solved

Cell joiner

You are given a cell array of strings and a string delimiter. You need to produce one string which is composed of each string fr...

3 years ago

Solved

Binary numbers

Given a positive, scalar integer n, create a (2^n)-by-n double-precision matrix containing the binary numbers from 0 through 2^n...

3 years ago

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Target sorting

Sort the given list of numbers |a| according to how far away each element is from the target value |t|. The result should return...

3 years ago

Solved

Balanced number

Given a positive integer find whether it is a balanced number. For a balanced number the sum of first half of digits is equal to...

3 years ago

Solved

What is the next step in Conway's Life?

Given a matrix A that represents the state of <http://en.wikipedia.org/wiki/Conway's_Game_of_Life Conway's game of Life> at one ...

3 years ago

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Remove the air bubbles

Given a matrix a, return a matrix b in which all the zeros have "bubbled" to the top. That is, any zeros in a given column shoul...

3 years ago

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Count from 0 to N^M in base N.

Return an array of numbers which (effectively) count from 0 to N^M-1 in base N. The result should be returned in a matrix, with ...

3 years ago

Solved

Distance walked 1D

Suppose you go from position 7 to 10 to 6 to 4. Then you have walked 9 units of distance, since 7 to 10 is 3 units, 10 to 6 is 4...

3 years ago

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Which values occur exactly three times?

Return a list of all values (sorted smallest to largest) that appear exactly three times in the input vector x. So if x = [1 2...

3 years ago

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Most nonzero elements in row

Given the matrix a, return the index r of the row with the most nonzero elements. Assume there will always be exactly one row th...

3 years ago

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Summing digits

Given n, find the sum of the digits that make up 2^n. Example: Input n = 7 Output b = 11 since 2^7 = 128, and 1 + ...

3 years ago

Solved

Multiply 2 numbers

Very easy, you just have to multiply 2 numbers but you cannot use the following signs (*, /, - ,^) ,mtimes , times, cross, pro...

3 years ago

Solved

Return a list sorted by number of occurrences

Given a vector x, return a vector y of the unique values in x sorted by the number of occurrences in x. Ties are resolved by a ...

3 years ago

Solved

Determine whether a vector is monotonically increasing

Return true if the elements of the input vector increase monotonically (i.e. each element is larger than the previous). Return f...

3 years ago

Solved

Check to see if a Sudoku Puzzle is Solved

*Description:* Your task, should you choose to accept it, is to make a function that checks to see if a 9x9 matrix of integer...

3 years ago

Solved

Roll the Dice!

*Description* Return two random integers between 1 and 6, inclusive, to simulate rolling 2 dice. *Example* [x1,x2] =...

3 years ago

Solved

Implement a counter

Write a function that returns a function that counts the number of times it is invoked. Example: >> h = counter; >> h() ...

3 years ago

Solved

Kaprekar Steps

6174 is the <http://en.wikipedia.org/wiki/6174_%28number%29 Kaprekar constant>. All natural numbers less than 10,000 (except som...

3 years ago

Solved

Swap the first and last columns

Flip the outermost columns of matrix A, so that the first column becomes the last and the last column becomes the first. All oth...

3 years ago

Solved

Say something funny

Say something funny, or not. Your solution will be (fully automatically and objectively) scored based on how clever or funny ...

3 years ago

Solved

Subset Sum

Given a vector v of integers and an integer n, return the the indices of v (as a row vector in ascending order) that sum to n. I...

3 years ago

Solved

Return the Nth Output from an Input Command

*Description* Given _F_, a cell array whose first element is a function handle and subsequent elements are arguments, return ...

3 years ago

Solved

Find a subset that divides the vector into equal halves

Given a vector x, return the indices to elements that will sum to exactly half of the sum of all elements. Example: Inpu...

3 years ago