Changing the number of rows in a vector by adding repeated rows

I have a vector V [76x3 double] and I want to make it V1 [1022x3 double].

I want to get the vector V1 in the following way:

-> rows 1:76 are the rows of vector V

-> rows 77:1022 are the rows of vector V placed randomly

How can it be obtained?

[Dyuman Joshi]

What do you mean by "missing rows"? Rows with zeros or nans? or otherwise? Please specify.

Do you want to add rows after the 76 rows or are some rows inbetween as well?

[Alberto Acri]

I have modified the question. I hope it is clearer now.

Answer 1

[Dyuman Joshi]

%V1 is 76x3 double
%random data
V1 = rand(76,3);
s = size(V1,1);
n = 1022;
%randomly sorted row indices from 1 to 76 to append
idx = randi(s,n-s,1)

idx = 946×1

66 44 65 72 10 21 47 41 8 74

%appending rows according to the indices
V1(s+1:n,:) = V1(idx,:);
size(V1)

ans = 1×2

1022 3

Answer 2

[Kevin Holly]

V = rand(76,3);
V1 = zeros(1064,3);
V1(1:76,:) = V;

for ii=1:13
    index = randperm(76);
    V1(76*ii+1:76*ii+76,:)= V(index,:);
end
V1 = V1(1:1022,:)

V1 = 1022×3

0.5613 0.6987 0.4500 0.9735 0.3625 0.3413 0.5039 0.4922 0.1920 0.9099 0.5943 0.0964 0.1295 0.0884 0.6340 0.0908 0.7025 0.3233 0.8137 0.0421 0.7189 0.9342 0.5742 0.5566 0.0371 0.4320 0.9536 0.7889 0.8865 0.2672