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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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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...

7 years ago

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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...

7 years ago

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Happy 2013...
Happy 2013, everyone! An interesting tidbit about 2013 is that it is the first year since 1987 to contain four different digits...

7 years ago

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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...

7 years ago

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Permute diagonal and antidiagonal
Permute diagonal and antidiagonal For example [1 2 3;4 5 6;7 8 9] -> [3 2 1;4 5 6;9 8 7] WITHOUT diag function (and variable n...

7 years ago

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Rotate input square matrix 90 degrees CCW without rot90
Rotate input matrix (which will be square) 90 degrees counter-clockwise without using rot90,flipud,fliplr, or flipdim (or eval)....

7 years ago

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Divisible by 2
This is the first problem in a set of "divisible by x" problems. You will be provided a number as a string and the function you ...

7 years ago

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The 5th Root
Write a function to find the 5th root of a number. It sounds easy, but the typical functions are not allowed (see the test su...

7 years ago

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Counting in Finnish
Sort a vector of single digit whole numbers alphabetically by their name, in Finnish. See the Wikipedia page for <http://en.wik...

7 years ago

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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

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Get the area codes from a list of phone numbers
Given a string of text with phone numbers in it, return a unique'd cell array of strings that are the area codes. s = '508-6...

7 years ago

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Find state names that start with the letter N
Given a list of US states, remove all the states that start with the letter N. If s1 = 'Alabama Montana Nebraska Vermont Ne...

7 years ago

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Calculate the Levenshtein distance between two strings
This problem description is lifted from <http://en.wikipedia.org/wiki/Levenshtein_distance>. The Levenshtein distance betwee...

7 years ago

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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

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Prime factor digits
Consider the following number system. Calculate the prime factorization for each number n, then represent the prime factors in a...

7 years ago

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(Linear) Recurrence Equations - Generalised Fibonacci-like sequences
This problem is inspired by problems <http://uk.mathworks.com/matlabcentral/cody/problems/2187-generalized-fibonacci 2187>, <htt...

7 years ago

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Iccanobif numbers 1
There are a lot of problems in Cody that deal with Fibonacci numbers (1, 1, 2, 3, 5, 8, 13, 21 etc...) so let's turn things arou...

7 years ago

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Fibonacci Decomposition
Every positive integer has a unique decomposition into nonconsecutive Fibonacci numbers f1+f2+ ... Given a positive integer n, r...

7 years ago

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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...

7 years ago

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Fibonacci-Sum of Squares
Given the Fibonacci sequence defined by the following recursive relation, * F(n) = F(n-1) + F(n-2) * where F(1) = 1 and F(1)...

7 years ago

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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 ...

7 years ago

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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

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Remove NaN ?
input -> matrix (n*m) with at least one element equal to NaN; output -> matrix(p*m), the same matrix where we deleted the enti...

7 years ago

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Decimal Comparison
*Background* A utility of particular interest to Cody and other MATLAB ventures is comparing the equality of two numbers. In ...

7 years ago

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Convert String to Morse Code
Convert a given string to international <http://en.wikipedia.org/wiki/Morse_code Morse Code> * Strings will only have [A-z], ...

7 years ago

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letter yes yes & letter no no
Split a string into two strings, wherein the first string has all alphabetic letters and the second string has all the remaining...

7 years ago

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String substitution, sub problem to cryptoMath
This is a sub problem related to this problem: <http://www.mathworks.com/matlabcentral/cody/problems/621-cryptomath-addition>...

7 years ago

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Pig Latin to English Translator
Pig latin is a faux-language based off of English. The rules are as follows (excerpted from the <http://en.wikipedia.org/wiki/Pi...

7 years ago

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Use of regexp
Given a string, containing several sentences, such as: 'I played piano. John played football. Anita went home. Are you safe?...

7 years ago

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