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How many Fibonacci numbers?
Find the number of unique Fibonacci numbers (don't count repeats) in a vector of positive integers. Example: x = [1 2 3 4...

5 years ago

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Matrix spiral
Make a spiral in a (n*n) matrix. The spiral has to start in the top left, and has to rotate clockwise to the center. The spiral ...

5 years ago

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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...

5 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....

5 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 ...

5 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,...

5 years ago

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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 : ...

5 years ago

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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 ...

5 years ago

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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...

5 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...

5 years ago

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Make a logical diamond using GALLERY function
Inspired from <http://www.mathworks.com/matlabcentral/cody/problems/1078-make-a-diamond Problem 1078. Make a diamond> In thi...

5 years ago

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

5 years ago

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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; ...

5 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...

5 years ago

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

5 years ago

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Divisible by n, Composite Divisors
Pursuant to <http://www.mathworks.com/matlabcentral/cody/problems/42453-divisible-by-n-prime-vs-composite-divisors Divisible by ...

5 years ago

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Divisible by n, Truncated-number Divisors
Some divisors only require a few numbers at the end of the number in question to determine divisibility, no matter how long. Exa...

5 years ago

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Divisible by n, prime divisors from 20 to 200
Pursuant to the previous problem (linked below), this problem requires a function that checks for divisibility of large numbers ...

5 years ago

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Divisible by n, prime divisors - 11, 13, 17, & 19
Divisibility checks against prime numbers can all be accomplished with the same routine, applied recursively, consisting of add ...

5 years ago

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Divisible by n, prime divisors (including powers)
For this problem, you will be provided an array of numbers (not necessarily in order). Return the array of numbers with only pri...

5 years ago

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Divisible by n, prime vs. composite divisors
In general, there are two types of divisibility checks; the first involves composite divisors and the second prime divisors, inc...

5 years ago

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Divisible by 16
Write a function to determine if a number is divisible by 16. This can be done by a few different methods. Here are two: # If...

5 years ago

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Divisible by 15
Write a function to determine if a number is divisible by 15. If a number is <http://www.mathworks.com/matlabcentral/cody/proble...

5 years ago

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Divisible by 14
Write a function to determine if a number is divisible by 14. If a number is <http://www.mathworks.com/matlabcentral/cody/proble...

5 years ago

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Divisible by 13
Write a function to determine if a number is divisible by 13. Similar to the number seven, this can be done by a few different m...

5 years ago

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Divisible by 12
Write a function to determine if a number is divisible by 12. Similar to the number six, this can be done by checking for divisi...

5 years ago

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Divisible by 7
Pursuant to the <http://www.mathworks.com/matlabcentral/cody/problems/42404-divisible-by-2 first problem> in this series, this o...

5 years ago

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Weave two matrices together to form one matrix
Take the first column from matrix a, then insert the first column from matrix b, and so on. For example: a = [1 2 3 4]; b ...

5 years ago

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Check if a rotated array was originally sorted
Suppose a sorted array is rotated at some pivot unknown to you. For example, |[0 1 2 4 5 6 7]| might become |[5 6 7 0 1 2 4]|. ...

5 years ago

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Zero Cross
Write a function that counts the number of times n a signal x changes sign. Examples x = [1 2 -3 -4 5 6 -7 8 -9 10 11] ...

5 years ago