Solved

Getting logical indexes

This is a basic MATLAB operation. It is for instructional purposes. --- Logical indexing works like this. thresh = 4...

12 months ago

Solved

Remove the two elements next to NaN value

The aim is to *remove the two elements next to NaN values* inside a vector. For example: x = [6 10 5 8 9 NaN 23 9 7 3 21 ...

12 months ago

Solved

Return a list sorted by number of consecutive occurrences

Inspired by Problem 38 by Cody Team. Given a vector x, return a vector y of the values in x sorted by the number of CONSECUTIVE...

12 months ago

Solved

Set the array elements whose value is 13 to 0

Input A either an array or a vector (which can be empty) Output B will be the same size as A . All elements of A equal to 13...

12 months ago

Solved

Joining Ranges

You are given a n-by-2 matrix. Each row represents a numeric range, e.g. x = [0 5; 10 3; 20 15; 16 19; 25 25] contains...

12 months ago

Solved

Find the largest value in the 3D matrix

Given a 3D matrix A, find the largest value. Example >> A = 1:9; >> A = reshape(A,[3 1 3]); >> islargest(A) a...

12 months ago

Solved

Get the elements of diagonal and antidiagonal for any m-by-n matrix

In the problem <http://www.mathworks.com/matlabcentral/cody/problems/858-permute-diagonal-and-antidiagonal Problem 858. Permute ...

12 months ago

Solved

Replicate elements in vectors

Replicate each element of a row vector (with NaN) a constant number of times. Examples n=2, A=[1 2 3] -> [1 1 2 2 3 3] ...

12 months ago

Solved

Morse Code Generator! Try it!

.... . .-.. .-.. --- . ...- . .-. -.-- --- -. . -.-.-- .-.. . - ... -.. --- ... --- -- . -- --...

12 months ago

Solved

Recurring Cycle Length (Inspired by Project Euler Problem 26)

Preface: This problem is inspired by <http://projecteuler.net/problem=26 Project Euler Problem 26> and uses text from that quest...

12 months ago

Solved

P-smooth numbers

This Challenge is to find <https://en.wikipedia.org/wiki/Smooth_number P-smooth number> partial sets given P and a max series va...

12 months ago

Solved

Fermat's Last Theorem - Fermat's conjecture

Fermat's Last Theorem (sometimes called Fermat's conjecture, especially in older texts) states that no three positive integers a...

12 months ago

Solved

Largest Twin Primes

<http://en.wikipedia.org/wiki/Twin_prime Twin primes> are primes p1, p2 = p1 + 2 such that both p1 and p2 are prime numbers. Giv...

12 months ago

Solved

Is it an Armstrong number?

An Armstrong number of three digits is an integer such that the sum of the cubes of its digits is equal to the number itself. Fo...

12 months ago

Solved

Champernowne Constant

The <http://en.wikipedia.org/wiki/Champernowne_constant Champernowne constant> is a real number whose digits in decimal represen...

12 months ago

Solved

Lychrel Number Test (Inspired by Project Euler Problem 55)

The task for this problem is to create a function that takes a number _n_ and tests if it might be a Lychrel number. This is, re...

12 months ago

Solved

First N Perfect Squares

*Description* Return the first N perfect squares *Example* input = 4; output = [ 1 4 9 16 ];

12 months ago

Solved

Numbers with prime factors 2, 3 and 5.

Make a function which takes one positive integer n and returns a matrix with the numbers of the form (2^i)*(3^j)*(5^k) which are...

12 months 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...

12 months ago

Solved

Determine if input is a perfect number

A <http://en.wikipedia.org/wiki/Perfect_number/ perfect number> occurs whent the sum of all divisors of a positive integer, exce...

12 months ago

Solved

Project Euler: Problem 9, Pythagorean numbers

A Pythagorean triplet is a set of three natural numbers, a b c, for which, a^2 + b^2 = c^2 For example, 3^2 + 4^2 =...

12 months ago

Solved

Determine if input is a Narcissistic number

<http://en.wikipedia.org/wiki/Narcissistic_number Narcissistic number> is a number that is the sum of its own digits each raised...

12 months ago

Solved

Mersenne Primes

A Mersenne prime is a prime number of the form M = 2^p - 1, where p is another prime number. For example, 31 is a Mersenne prim...

12 months ago

Solved

arithmetic progression

I've written a program to generate the first few terms of <https://en.wikipedia.org/wiki/Arithmetic_progression arithmetic progr...

1 year ago

Solved

Find similar sequences

Another problem inspired by a question on the <http://www.mathworks.com/matlabcentral/answers answers> forum. Given a matrix ...

1 year ago

Solved

Sum of series VII

What is the sum of the following sequence: Σ(km^k)/(k+m)! for k=1...n for different n and m?

1 year ago

Solved

Sum of series VI

What is the sum of the following sequence: Σk⋅k! for k=1...n for different n?

1 year ago

Solved

Sum of series V

What is the sum of the following sequence: Σk(k+1) for k=1...n for different n?

1 year ago

Solved

Sum of series IV

What is the sum of the following sequence: Σ(-1)^(k+1) (2k-1)^2 for k=1...n for different n?

1 year ago

Solved

Sum of series III

What is the sum of the following sequence: Σ(2k-1)^3 for k=1...n for different n?

1 year ago