Community Profile

photo

Roy Mathew


MathWorks

44 total contributions since 2012

Contact

Roy Mathew's Badges

  • Quiz Master
  • Creator
  • Promoter
  • Solver

View details...

Contributions in
View by

Solved


Make a half wave rectifier
Produce a signal that outputs the given sine wave source when it is greater than zero and outputs zero when it is less than zero...

4 years ago

Solved


Produce a cosine wave
Produce the following signal: <<http://blogs.mathworks.com/images/seth/cody/cosine-eqn.png>>

4 years ago

Solved


Tell me the slope
Tell me the slope, given a vector with horizontal run first and vertical rise next. Example input: x = [10 2];

6 years ago

Solved


Encoding Google Maps Polylines
This problem is based on the Google Polyline Encoder algorithm. This is how Google Maps encodes a line for display on a map. You...

7 years ago

Solved


Longest Divisor Run
Given the vector a, find the longest run of consecutive numbers that can be evenly divided by the same number d where d > 1. ...

7 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...

7 years ago

Solved


Bullseye Matrix
Given n (always odd), return output a that has concentric rings of the numbers 1 through (n+1)/2 around the center point. Exampl...

7 years ago

Solved


Is X a Fibonacci Matrix?
In honor of Cleve's new blog and post: <http://blogs.mathworks.com/cleve/2012/06/03/fibonacci-matrices/> Is X a Fibonacci ...

7 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...

7 years ago

Solved


Find the peak 3n+1 sequence value
A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...

7 years ago

Solved


It dseon't mettar waht oedrr the lrettes in a wrod are.
An internet meme from 2003 (read more <http://www.snopes.com/language/apocryph/cambridge.asp here>) asserted that readers are re...

7 years ago

Solved


QWERTY coordinates
Given a lowercase letter or a digit as input, return the row where that letter appears on a <http://en.wikipedia.org/wiki/Keyboa...

7 years ago

Solved


Find common elements in matrix rows
Given a matrix, find all elements that exist in every row. For example, given A = 1 2 3 5 9 2 5 9 3 2 5 9 ...

7 years ago

Solved


Scrabble Scores
Given a word, determine its score in <http://en.wikipedia.org/wiki/Scrabble Scrabble>. The input string will always be provide...

7 years ago

Solved


Which doors are open?
There are n doors in an alley. Initially they are all shut. You have been tasked to go down the alley n times, and open/shut the...

7 years ago

Solved


Summing Digits within Text
Given a string with text and digits, add all the numbers together. Examples: Input str = '4 and 20 blackbirds baked in a...

7 years ago

Solved


Function Iterator
Given a handle fh to a function which takes a scalar input and returns a scalar output and an integer n >= 1, return a handle f...

7 years ago

Solved


Sums with Excluded Digits
Add all the integers from 1 to n in which the digit m does not appear. m will always be a single digit integer from 0 to 9. no...

7 years ago

Solved


Extract leading non-zero digit
<http://en.wikipedia.org/wiki/Benford%27s_law Benford's Law> states that the distribution of leading digits is not random. This...

7 years ago

Solved


Elapsed Time
Given two date strings d1 and d2 of the form yyyy/mm/dd HH:MM:SS (assume hours HH is in 24 hour mode), determine how much time, ...

7 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...

7 years ago

Solved


Find the longest sequence of 1's in a binary sequence.
Given a string such as s = '011110010000000100010111' find the length of the longest string of consecutive 1's. In this examp...

7 years ago

Solved


Greed is good - Simple partition P[n].
Find a simple partition P[n]. E.g. P[10] = 4 + 3 + 2 + 1. # There are many solutions, compute just one set. # Don't repeat ...

7 years ago

Solved


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...

7 years ago

Solved


Remove all the consonants
Remove all the consonants in the given phrase. Example: Input s1 = 'Jack and Jill went up the hill'; Output s2 is 'a ...

7 years ago

Solved


Spot the rectangle
This problem is related to the <http://bit-player.org/2009/the-17x17-challenge 17x17 challenge>. Given a matrix filled with ones...

7 years ago

Solved


Pascal's Triangle
Given an integer n >= 0, generate the length n+1 row vector representing the n-th row of <http://en.wikipedia.org/wiki/Pascals_t...

7 years ago

Solved


Find the alphabetic word product
If the input string s is a word like 'hello', then the output word product p is a number based on the correspondence a=1, b=2, ....

7 years ago

Solved


Project Euler: Problem 6, Natural numbers, squares and sums.
The sum of the squares of the first ten natural numbers is, 1^2 + 2^2 + ... + 10^2 = 385 The square of the sum of the first ...

7 years ago

Solved


Project Euler: Problem 7, Nth prime
By listing the first six prime numbers: 2, 3, 5, 7, 11, and 13, we can see that the 6th prime is 13. What is the Nth prime nu...

7 years ago

Load more