237 total contributions since 2009

PhD in Applied mathematics from the University of Nottingham.

Work in the Energy industry

Solved

Make an awesome ramp for a tiny motorcycle stuntman

Okay, given a vector, say v=[1 3 6 9 11], turn it into a matrix 'ramp' like so: m=[1 3 6 9 11; 3 6 9 11 0; 6 9 ...

1 year 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...

1 year ago

Solved

Get the length of a given vector

Given a vector x, the output y should equal the length of x.

1 year ago

Solved

Back to basics 6 - Column Vector

Covering some basic topics I haven't seen elsewhere on Cody. Given an input vector, output true or false whether it is a colu...

1 year ago

Solved

Solve the Sudoku Row

*Description* A simple yet tedious task occurs near the end of most Sudoku-solving algorithms, computerized or manual. The ta...

1 year ago

Solved

Find best placement for ordered dominoes (harder)

Given a list of ordered pairs, find the order they should be placed in a line, such that the sum of the absolute values of the d...

1 year ago

Solved

Find perfect placement of non-rotating dominoes (easier)

Given a list of ordered pairs, find the order they should be placed in a line, such that the sum of the absolute values of the d...

1 year 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...

1 year 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...

1 year 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...

1 year ago

Solved

Indexed Probability Table

This question was inspired by a Stack Overflow question forwarded to me by Matt Simoneau. Given a vector x, make an indexed pro...

1 year ago

Solved

Armstrong Number

Determine whether the given input n-digit number is Armstrong Number or not. Return True if it is an Armstrong Number. An n-D...

1 year ago

Solved

Find the two most distant points

Given a collection of points, return the indices of the rows that contain the two points most distant from one another. The inpu...

1 year ago

Solved

Pattern matching

Given a matrix, m-by-n, find all the rows that have the same "increase, decrease, or stay same" pattern going across the columns...

1 year ago

Solved

Find the sum of the elements in the "second" diagonal

Find the sum of the elements in the diagonal that starts at the top-right corner and ends at the bottom-left corner.

1 year ago

Solved

Make a Palindrome Number

Some numbers like 323 are palindromes. Other numbers like 124 are not. But look what happens when we add that number to a revers...

1 year ago

Solved

Rotate and display numbered tile

Imagine a square tile with four numbers on it, one on each edge. We will call these edges north, east, south, and west. If th...

1 year ago

Solved

Connect blocks in a model

Connect the blocks in the model to produce the following signal: <<http://blogs.mathworks.com/images/seth/cody/connect-blocks...

1 year ago

Solved

Trimming Spaces

Given a string, remove all leading and trailing spaces (where space is defined as ASCII 32). Input a = ' singular value deco...

1 year ago

Solved

Compute Fibonacci Number

Compute the _n_-th Fibonacci Number f(0) = 0, f(1) = 1, f(2) = 1, f(3) = 2, ... f(42) = 267914296

1 year ago

Solved

Determine if a Given Number is a Triangle Number

*Description:* Determine if the elements of an input array are triangle numbers and return the result as an array with the sa...

1 year ago

Solved

Project Euler: Problem 1, Multiples of 3 and 5

If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23...

1 year ago

Solved

Stuff the Board

You have a stack of tiles to put onto an array-like playing board. Each tile has a number (always an integer), and the board var...

1 year ago

Solved

Twist 'n' Match

Given n and m, construct an n-by-n matrix a such that a, when rotated 90 degrees and compared with itself, matches itself in exa...

1 year ago

Solved

Angle between Two Vectors

The dot product relationship, a dot b = | a | | b | cos(theta), can be used to determine the acute angle between vector a and ve...

1 year ago

Solved

Angle between two vectors

You have two vectors , determine the angle between these two vectors For example: u = [0 0 1]; v = [1 0 0]; The a...

1 year ago

Solved

Right and wrong

Given a vector of lengths [a b c], determines whether a triangle with those sides lengths is a right triangle: <http://en.wikipe...

1 year ago

Solved

Number of 1s in the Binary Representation of a Number

*Description* Return the number of 1s in the (unsigned integer) binary representation of a number. This function should be ab...

1 year ago

Solved

Increment a number, given its digits

Take as input an array of digits (e.g. x = [1 2 3]) and output an array of digits that is that number "incremented" properly, (i...

1 year ago

Solved

Sum of diagonal of a square matrix

If x = [1 2 4; 3 4 5; 5 6 7] then y should be the sum of the diagonals of the matrix y = 1 + 4 + 7 = 12

1 year ago