MATLAB: Converting 1*4 array into 1*1

Question

hi,

I have an array a=[1 2 3 4] with dimension 1*4 and i want it to convert into

value 1234 of size 1*1 double.

other example : a=[4 5 6 7 8 9] size 1*6 , convert into 456789 , size 1*1 double.

Answer 1

a=[1 2 3 4];
b=num2str(a);
b(b==' ')=[];
out=str2num(b)