how to multiply simplest way this two vectors ?

I have to multiply this xi and y this way:

xi = [98 99 100 101 102 103]; y = [2 4 6 4 3 1]; x = [ 98*ones(1,2), 99*ones(1,4), 100*ones(1,6), 101*ones(1,4),... 102*ones(1,3), 103*ones(1,1) ]

it is possible to somthing this to make.... x = xi.*( ones(1,y(1:end)) ) % this is not working

[Stephen23]

Note that this is array replication , not multiplication .

Answer 1

[Azzi Abdelmalek]

xi = [98 99 100 101 102 103];
y =  [2  4  6   4   3   1];
x=cell2mat(arrayfun(@(a,b) a*ones(1,b),xi,y,'un',0))

%or you can do it just by using a for loop

Answer 2

[Guillaume]

This is not a multiplication.

One of many ways to do what you want:

xi = [98 99 100 101 102 103]; 
y = [2 4 6 4 3 1];
x = cell2mat(arrayfun(@(v, r) repmat(v, 1, r), xi, y, 'UniformOutput', false))

Answer 3

[Andrei Bobrov]

a = accumarray(cumsum([1; y(:)]),1);
x = xi(cumsum(a(1:end-1)));