# select few values from a vector randomly

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Elysi Cochin on 1 Feb 2023
Edited: Tushar Behera on 1 Feb 2023
v1 = [3 4 7 14 15 18 23 25 28 31 34 36 37 38 39 40 42 44 46];
v2 = [1 2 5 6 8 9 10 11 12 13 16 17 19 20 21 22 24 26 27 29 30 32 33 35 41 43 45 47];
I have 2 vectors v1 and v2
v1 has 19 columns and v2 has 28 columns
I wanted to create a new vector v of size 25 with all elements of v1 and if the size of v is not 25 I need to select few numbers from v2 randomly so as to make the size of v = 25 and write it in a sorted order

Arif Hoq on 1 Feb 2023
try this:
v1 = [3 4 7 14 15 18 23 25 28 31 34 36 37 38 39 40 42 44 46];
v2 = [1 2 5 6 8 9 10 11 12 13 16 17 19 20 21 22 24 26 27 29 30 32 33 35 41 43 45 47];
target=25;
matsise=numel(v2);
a=v2(randperm(matsise,target -length(v1)));
v=sort([v1 a],'ascend')
v = 1×25
3 4 6 7 8 14 15 18 19 23 25 28 29 30 31 34 35 36 37 38 39 40 42 44 46

### More Answers (1)

Tushar Behera on 1 Feb 2023
Edited: Tushar Behera on 1 Feb 2023
Are you looking for something like this
v1 = [3 4 7 14 15 18 23 25 28 31 34 36 37 38 39 40 42 44 46];
v2 = [1 2 5 6 8 9 10 11 12 13 16 17 19 20 21 22 24 26 27 29 30 32 33 35 41 43 45 47];
v1=unique(v1);
v2=unique(v2);
num1=numel(v1);
num2=numel(v2);
v=zeros(1,25);
v=[v1]
if num1<25
for i=(num1+1):25
index = randi(numel(v2));
randomElement = v2(index);
if ismember(randomElement,v1)
%do nothing
else
v(i)=randomElement;
end
end
end
v=sort(v)
##### 2 CommentsShow 1 older commentHide 1 older comment
Tushar Behera on 1 Feb 2023
take a look at the edited answer

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