matlab - Construct a matrix from a vector periodically -


this question has answer here:

i have vectorb 30 entries.

i want avoid using for loop construct matrix this:

enter image description here

where b_i i-th entry of vector b.

for example, define vector

b = [2 6 -7 3 1 -4 -1  1 11  8 -4  9  2  0  2 -1  0  4  4  4  2 -4  2  5  1 3  2 -1  1 -2]

where tried using loop is:

a = zeros(5,5); = 1:5     a(i) = b(i+5);     a(i+5) = b(i+6);     a(i+10) = b(i+7);     a(i+15) = b(i+8);     a(i+20) = b(i+9); end

the result

enter image description here

is there faster , more general method generate matrix?

you can use toeplitz:

a=fliplr(toeplitz(b(10:14),b(10:-1:6))  =  -4    -1     1    11     8 -1     1    11     8    -4  1    11     8    -4     9 11     8    -4     9     2  8    -4     9     2     0

by way, indices here 6 14 in example, , not 7 15 in picture. can change preferred purpose.


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