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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)....

6 months ago

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Removing rows from a matrix is easy - but what about inserting rows?
Assume A is a 5-by-5 matrix. A([2,4],:) = [] is a quick way to remove rows 2 and 4. Can you find a quick way to insert rows into...

6 months ago

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Matrix with different incremental runs
Given a vector of positive integers a = [ 3 2 4 ]; create the matrix where the *i* th column contains the vector *1:a(i)...

6 months ago

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Set some matrix elements to zero
First get the maximum of each *row*, and afterwards set all the other elements to zero. For example, this matrix: 1 2 3 ...

6 months ago

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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 ...

6 months 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 ...

6 months ago

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Back to basics 23 - Triangular matrix
Covering some basic topics I haven't seen elsewhere on Cody. Given an input matrix, return a matrix with all elements above a...

6 months ago

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N-Dimensional Array Slice
Given an N-dimensional array, _A_, an index, _I_, and a dimension, _d_, return the _I_ th elements of _A_ in the _d_ dimension. ...

6 months 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...

6 months 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...

6 months ago

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Back to basics 21 - Matrix replicating
Covering some basic topics I haven't seen elsewhere on Cody. Given an input matrix, generate an output matrix that consists o...

6 months ago

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sum of non-primes
The sum of the non-primes no larger than 10 is 1+4+6+8+9+10=38 Find the sum of all the positive non-prime integers that do no...

6 months ago

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subtract central cross
Given an n-by-n square matrix, where n is an odd number, return the matrix without the central row and the central column.

6 months ago

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Nilpotent matrix
Check if matrix A is <http://mathworks.com/ nilpotent>.

6 months ago

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surrounded matrix
With a given matrix A (size m x n) create a matrix B (size m+2 x n+2) so that the matrix A is surrounded by ones: A = [1 2 ...

6 months ago

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Spherical Volume
Calculate the volume of a sphere.

6 months ago

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Area of a Square
Given the length x of the side of a regular square, find the area of the square, A.

6 months ago

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Given a number N, find the smallest prime P>N
Given a number N, find the smallest prime P greater than N. For example: If N=10 then P=11. If N=13 then P=17.

6 months ago

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area of an annulus
Given the diameter d of the inner circle of the annulus. Given length z of a chord of the outer circle of the annulus. This chor...

6 months ago

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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...

6 months ago

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Longest run of consecutive numbers
Given a vector a, find the number(s) that is/are repeated consecutively most often. For example, if you have a = [1 2 2 2 1 ...

6 months ago

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Rescale Scores
Each column (except last) of matrix X contains students' scores in a course assignment or a test. The last column has a weighted...

6 months ago

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Calculate Inner Product
Given two input matrices, x and y, check if their inner dimensions match. If they match, create an output variable z which cont...

6 months ago

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Find MPG of Lightest Cars
The file cars.mat contains a table named cars with variables Model, MPG, Horsepower, Weight, and Acceleration for several classi...

6 months ago

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Find the Best Hotels
Given three input variables: hotels - a list of hotel names ratings - their ratings in a city cutoff - the rating at which yo...

6 months ago

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Crop an Image
A grayscale image is represented as a matrix in MATLAB. Each matrix element represents a pixel in the image. An element value re...

6 months ago

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Calculate BMI
Given a matrix hw (height and weight) with two columns, calculate BMI using these formulas: 1 kilogram = 2.2 pounds 1 inch = 2...

6 months ago

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Plot Damped Sinusoid
Given two vectors |t| and |y|, make a plot containing a blue ( |b| ) dashed ( |--| ) line of |y| versus |t|. Mark the minimum...

6 months ago

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Calculate a Damped Sinusoid
The equation of a damped sinusoid can be written as y = A.ⅇ^(-λt)*cos(2πft) where A, λ, and f are scalars and t is a vector. ...

6 months ago

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Solve a System of Linear Equations
Example: If a system of linear equations in x₁ and x₂ is: 2x₁ + x₂ = 2 x₁ - 4 x₂ = 3 Then the coefficient matrix (A) is: 2 ...

6 months ago