Solved

Back to basics 20 - singleton dimensions
Covering some basic topics I haven't seen elsewhere on Cody. Remove the singleton dimensions from the input variable (e.g. if...

14 years ago

Problem

Flip the main diagonal of a matrix
Given a n x n matrix, M, flip its main diagonal. Example: >> M=magic(5); >> flipDiagonal(M) 9 24 1 ...

14 years ago | 7 | 901 solvers

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

Flip the main diagonal of a matrix
Given a n x n matrix, M, flip its main diagonal. Example: >> M=magic(5); >> flipDiagonal(M) 9 24 1 ...

14 years ago

Solved

Sum all integers from 1 to 2^n
Given the number x, y must be the summation of all integers from 1 to 2^x. For instance if x=2 then y must be 1+2+3+4=10.

14 years ago

Problem

Create a square matrix of multiples
Given an input, N, output a matrix N x N with each row containing multiples of the first element of each row. This also applies...

14 years ago | 3 | 495 solvers

Solved

Create a square matrix of multiples
Given an input, N, output a matrix N x N with each row containing multiples of the first element of each row. This also applies...

14 years ago

Solved

Make a checkerboard matrix
Given an integer n, make an n-by-n matrix made up of alternating ones and zeros as shown below. The a(1,1) should be 1. Example...

14 years ago

Problem

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

14 years ago | 6 | 1660 solvers

Solved

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

14 years ago

Solved

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

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...

14 years ago

Solved

Figurate number triangle
Check whether the input matrix is a figurate number triangle: <http://mathworld.wolfram.com/FigurateNumberTriangle.html>

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

Sort a list of complex numbers based on far they are from the origin.
Given a list of complex numbers z, return a list zSorted such that the numbers that are farthest from the origin (0+0i) appear f...

14 years ago

Solved

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; ...

14 years ago

Solved

Is my wife right?
Regardless of input, output the string 'yes'.

14 years ago

Solved

Find the sum of the elements in the "second" diagonal
Find the sum of the elements in the diagonal that starts at the top-right corner and ends at the bottom-left corner.

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

Problem

Find the Kronecker Tensor Product without using KRON
The Kronecker Tensor Product is the result of multiplying all elements of a matrix with each of the elements of another matrix. ...

14 years ago | 2 | 49 solvers

Problem

Solve the set of simultaneous linear equations
Given this pair of simultaneous linear equations: 2x + 3y = 23 3x + 4y = 32 Find the solution set (x,y)

14 years ago | 4 | 491 solvers

Solved

Find the Kronecker Tensor Product without using KRON
The Kronecker Tensor Product is the result of multiplying all elements of a matrix with each of the elements of another matrix. ...

14 years ago

Solved

Finding Perfect Squares
Given a vector of numbers, return true if one of the numbers is a square of one of the other numbers. Otherwise return false. E...

14 years ago

Solved

Pizza!
Given a circular pizza with radius _z_ and thickness _a_, return the pizza's volume. [ _z_ is first input argument.] Non-scor...

14 years ago

Solved

The Hitchhiker's Guide to MATLAB
Output logical "true" if the input is the answer to life, the universe and everything. Otherwise, output logical "false".

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

Check if sorted
Check if sorted. Example: Input x = [1 2 0] Output y is 0

14 years ago

Solved

Return the largest number that is adjacent to a zero
This example comes from Steve Eddins' blog: <http://blogs.mathworks.com/steve/2009/05/27/learning-lessons-from-a-one-liner/ Lear...

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

Problem

What is the distance from point P(x,y) to the line Ax + By + C = 0?
Given a point, P(x,y), find the distance from this point to a linear line. INPUTS: x, y, A, B, C OUTPUTS: d, the distance ...

14 years ago | 5 | 554 solvers