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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. ...
18日 前
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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...
18日 前
解決済み
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)...
19日 前
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Operate on matrices of unequal, yet similar, size
You may want to add a vector to a matrix, implying that the vector is added to each column of the matrix. Or multiply a 3x4x5 ma...
19日 前
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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...
19日 前
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Reverse the elements of an array
Reverse the order of elements in an array: eg: input X = [ 1 2 3 ; 4 5 6 ; 7 8 9 ] o...
19日 前
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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 ...
20日 前
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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...
20日 前
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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)....
20日 前
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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 ...
20日 前
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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 ...
20日 前
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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...
20日 前
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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...
20日 前
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Matrix multiplication across rows
Given matrix m, return matrix n such that, rows of n are result of multiplication of the rows of the input matrix Example ...
24日 前
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Enlarge array
Given an m-by-n numeric array (A) and a 1-by-2 vector (sz) indicating the dimensions [p q] to enlarge each element, return an (m...
25日 前
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A matrix of extroverts
Now that the introverts have had their script, the extroverts spoke up (naturally!) and demanded one as well. You will be given...
25日 前
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Too Many Zeros, Dump Them!
Sometimes when I create a matrix, I use this syntax: a = zeros(1000,1000); But when the function ends, I find that I don'...
25日 前
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Given a matrix, swap the 2nd & 3rd columns
If a = [1 2 3 4; 1 2 3 4; 1 2 3 4; 1 2 3 4]; then the result is ans = 1 3 2 4 1 3 2...
26日 前
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linear least squares fitting
Inputs: * |f|: cell-array of function handles * |x|: column vector of |x| values * |y|: column vector of |y| values, same l...
27日 前
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Projector Matrix
Write a function to determine whether or not the matrix is a projector. Projector matrices are defined as P^2 = P.
27日 前
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Orthonormal matrix
You decide whether any given matrix is an orthonormal matrix or not. If each column in a matrix is perpendicular to the other...
27日 前
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Determine if input is a valid AHP evaluation matrix
Input is a matrix. Output is a true or false statement (1 or 0). Return true if input is a valid Analytic Hierarchy Process eval...
28日 前
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Combined Ages 4 - Non-symmetric with multiples, n ≥ 3
This problem is slightly more difficult than <http://www.mathworks.com/matlabcentral/cody/problems/42383-combined-ages-3-non-sym...
28日 前
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Combined Ages 3 - Non-symmetric, n ≥ 3
Pursuant to the previous two problems ( <http://www.mathworks.com/matlabcentral/cody/problems/42382-combined-ages-1-symmetric-n-...
28日 前
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Combined Ages 2 - Symmetric, n ≥ 3
Following on <http://www.mathworks.com/matlabcentral/cody/problems/42382-combined-ages-1-symmetric-n-3 Combined Ages 2>, you wil...
29日 前
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Combined Ages 1 - Symmetric, n = 3
You have probably seen the common riddle wherein combined ages are provided and you must determine the individual ages. For exam...
29日 前
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Outer product of multiple vectors
In tensor algebra, it is often useful to define a tensor as a product of lower order tensors. Similarly, a multidimensional arra...
29日 前
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Is this matrix orthogonal?
Given a square matrix, a, determine whether it is orthogonal. INPUT: a, a n x n matrix OUTPUT: true or false
29日 前
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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)
29日 前