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 : ...

14 years ago

Solved

Make a run-length companion vector
Given a vector x, return a vector r that indicates the run length of any value in x. Each element in r shows how many times the ...

14 years ago

Solved

N-Cards Problem
You have a deck of _N_ cards numbered in order from 1 to _N_. You discard the top card (card 1) and place the next card (card 2)...

14 years ago

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Spot the outlier
All points except for one lie on a line. Which one is the outlier? Example: You are given a list of x-y pairs in a column ...

14 years ago

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How many trades represent all the profit?
Given a list of results from trades made: [1 3 -4 2 -1 2 3] We can add them up to see this series of trades made a profit ...

14 years ago

Solved

Cell joiner
You are given a cell array of strings and a string delimiter. You need to produce one string which is composed of each string fr...

14 years ago

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Ackermann's Function
Ackermann's Function is a recursive function that is not 'primitive recursive.' <http://en.wikipedia.org/wiki/Ackermann_fun...

14 years ago

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Roll the Dice!
*Description* Return two random integers between 1 and 6, inclusive, to simulate rolling 2 dice. *Example* [x1,x2] =...

14 years ago

Solved

Vectorize the digits of an Integer
Create a vector of length N for an integer of N digits. x=123045; x_vec=[1 2 3 0 4 5]; I happened upon a trick to do ...

14 years ago

Solved

Given an unsigned integer x, find the largest y by rearranging the bits in x
Given an unsigned integer x, find the largest y by rearranging the bits in x. Example: Input x = 10 Output y is 12 ...

14 years ago

Solved

Magic!
Check whether the input matrix is a normal magic square: <http://en.wikipedia.org/wiki/Magic_square> Output the logical va...

14 years ago

Solved

DNA N-Gram Distribution
Given a string s and a number n, find the most frequently occurring n-gram in the string, where the n-grams can begin at any poi...

14 years 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...

14 years ago

Solved

Is my wife right? Now with even more wrong husband
Again, as in "Is my wife right?" ( <http://www.mathworks.com/matlabcentral/cody/problems/149-is-my-wife-right> ), answer 'yes' r...

14 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 ...

14 years ago

Solved

Determine Whether an array is empty
Input a matrix x, output y is TRUE if x is empty, otherwise FALSE.

14 years ago

Solved

Pangrams!
A pangram, or holoalphabetic sentence, is a sentence using every letter of the alphabet at least once. Example: Input s ...

14 years ago

Solved

Parcel Routing
Given a matrix that represent the distance along highways between major cities numbered 1 to _N_, provide the path and shortest ...

14 years 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...

14 years 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...

14 years ago

Solved

Distance walked 1D
Suppose you go from position 7 to 10 to 6 to 4. Then you have walked 9 units of distance, since 7 to 10 is 3 units, 10 to 6 is 4...

14 years ago

Solved

Too mean-spirited
Find the mean of each consecutive pair of numbers in the input row vector. For example, x=[1 2 3] ----> y = [1.5 2.5] x=[1...

14 years ago

Solved

Check to see if a Sudoku Puzzle is Solved
*Description:* Your task, should you choose to accept it, is to make a function that checks to see if a 9x9 matrix of integer...

14 years ago

Solved

The Goldbach Conjecture
The <http://en.wikipedia.org/wiki/Goldbach's_conjecture Goldbach conjecture> asserts that every even integer greater than 2 can ...

14 years ago

Solved

Is A the inverse of B?
Given a matrix A and a matrix B, is A the inverse of B? >>A=[2,4;3,5]; >>B=[-2.5,2;1.5,-1]; >>isInverse...

14 years ago

Solved

Summing digits
Given n, find the sum of the digits that make up 2^n. Example: Input n = 7 Output b = 11 since 2^7 = 128, and 1 + ...

14 years ago

Solved

Return the 3n+1 sequence for n
A Collatz sequence is the sequence where, for a given number n, the next number in the sequence is either n/2 if the number is e...

14 years ago

Solved

Back and Forth Rows
Given a number n, create an n-by-n matrix in which the integers from 1 to n^2 wind back and forth along the rows as shown in the...

14 years ago

Solved

Find the numeric mean of the prime numbers in a matrix.
There will always be at least one prime in the matrix. Example: Input in = [ 8 3 5 9 ] Output out is 4...

14 years ago

Solved

Remove any row in which a NaN appears
Given the matrix A, return B in which all the rows that have one or more <http://www.mathworks.com/help/techdoc/ref/nan.html NaN...

14 years ago