MATLAB: How to efficiently create a vector

create vectorefficientmatrix table

I want create a matrix such that

A matrix mat_B = [ 1 2 3 4 5; 6 7 8 9 10; 11 12 13 14 15; 16 17 18 19 20].

Is there any other code that more efficient than the code I make below?

for i = 1:5 if i ==1 a (i,:)=1:4; else a (i,:) = (a (i-1,:))+4; end end

Best Answer

I would use the reshape function to avoid the explicit loops:

v = 1:20;
mat_B = reshape(v, 5, [])';

Related Solutions

MATLAB: How to reshape a 2D to 3D matrix without using loops (reshape) and keeping a particular order of the elements// Wrong arragement of elemts after using “reshape”

   A=[1     2     3     4
     5     6     7     8
     9    10    11    12
    13    14    15    16
     1     2     3     4
     5     6     7     8
     9    10    11    12
    13    14    15    16
     1     2     3     4
     5     6     7     8
     9    10    11    12
    13    14    15    16]
A2=permute(reshape(A',4,4,[]),[2 1 3])

MATLAB: How to modify vector

What vector? Is x a vector? Why do you possibly need a while loop?

y = y + round(rand(size(y))) - 0.5;

So round(rand(size(y))) is randomly 0 or 1, with 50% chance for either. Subtract 1/2, and you will effectively randomly add or subtract .5.

Best Answer

Related Solutions

MATLAB: How to reshape a 2D to 3D matrix without using loops (reshape) and keeping a particular order of the elements// Wrong arragement of elemts after using “reshape”

MATLAB: How to modify vector

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