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Slicing the cube
A bored matlab enthusiast has a cube with volume n^3. He decides to paint the entire surface of the cube red. Then, with slices...

7 years ago

Solved

5 Prime Numbers
Your function will be given lower and upper integer bounds. Your task is to return a vector containing the first five prime numb...

7 years ago

Solved

Pernicious Anniversary Problem
Since Cody is 5 years old, it's pernicious. A <http://rosettacode.org/wiki/Pernicious_numbers Pernicious number> is an integer w...

7 years ago

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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...

7 years ago

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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...

7 years ago

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Sophie Germain prime
In number theory, a prime number p is a *Sophie Germain prime* if 2p + 1 is also prime. For example, 23 is a Sophie Germain prim...

7 years ago

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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...

7 years ago

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What percentage?
Calculate the output c as the percentage of a on b for given a and b.

7 years ago

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Back to basics 22 - Rotate a matrix
Covering some basic topics I haven't seen elsewhere on Cody. Rotate the input matrix 90 degrees counterclockwise (e.g. [1 2; ...

7 years ago

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

7 years ago

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Spiral In
Create an m by n matrix filled with sequential integers starting from 1 and arranged in a counterclockwise spiral that hugs the ...

7 years ago

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Spot the rectangle (Part 2)
This problem is related to the <http://bit-player.org/2009/the-17x17-challenge 17x17 challenge>. See also <http://www.mathworks....

7 years ago

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Create a patchwork matrix
This function will assemble a large matrix out of a number of smaller ones m1, m2, etc., according to a pattern P. If P is 3x5,...

7 years ago

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Create Volcano (or Atoll) martix. It is an extension of Bullseye matrix problem.
For example, if n=2 (maximum value), the output matrix should be [1 1 1 1 1; 1 2 2 2 1; 1 2 1 2 1; 1 2 2 2 1; 1...

7 years ago

Solved

Mirror Image matrix across anti-diagonal
Given an input number x, create a mirror image matrix 'Y' across the anti-diagonal. For example, if x=3, Y = [1 2 3; ...

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 Matrix
Given an integer n ≥ 0, generate the ( _n_+1) × ( _n_+1) lower triangular <http://en.wikipedia.org/wiki/Pascal_matrix P...

7 years ago

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Make a Star Pyramid
Create a star pyramid. First line will have 1 star, second will have two stars and so on... a basic program which is easily done...

7 years ago

Solved

Create a matrix X, where each column is a shifted copy of the vector v
Example : in->v = (1:5)'; 1 2 3 4 5 out-> [1 5 4 3 2;2 1 5 4 3;3 2 1 5 4;4 3 2 1 5;5 4 3 ...

7 years ago

Solved

Symmetric matrix
You must create a n-by-n *symmetric* matrix such that A(row,col) = row/col for col >= row. Example if n =3 : output is : ...

7 years ago

Solved

Special matrix
Make a square matrix with this shape. For n=4 M = 1 1 0 0 1 0 1 0 0 1 0 ...

7 years ago

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Better bullseye matrix
<http://www.mathworks.com/matlabcentral/cody/problems/18-bullseye-matrix Problem 18> asks to create a bullseye matrix like this:...

7 years ago

Solved

Create a Multiplication table matrix...
Create a product table in this format: P = [ 1 2 3 4 5; 2 4 6 8 10; 3 6 9 12 15; 4 8 12 1...

7 years ago

Solved

Square Digits Number Chain Terminal Value (Inspired by Project Euler Problem 92)
Given a number _n_, return the terminal value of the number chain formed by summing the square of the digits. According to the P...

7 years ago

Solved

Project Euler: Problem 2, Sum of even Fibonacci
Each new term in the Fibonacci sequence is generated by adding the previous two terms. By starting with 1 and 2, the first 10 te...

7 years ago

Solved

Replace NaNs with the number that appears to its left in the row.
Replace NaNs with the number that appears to its left in the row. If there are more than one consecutive NaNs, they should all ...

8 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 ...

8 years ago

Solved

Are you in or are you out?
Given vertices specified by the vectors xv and yv, and a single point specified by the numbers X and Y, return "true" if the poi...

8 years 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...

8 years ago

Solved

Y=X
Given an input variable x, output a variable y that is equal in value to x. Example: Input x = 1 Output y is 1 Inp...

8 years ago