# create a vector without for

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saihua lin on 19 Jan 2020
Commented: Stephen Cobeldick on 19 Jan 2020
The vector structure is like [a b c d e f g h i j]
a=1:10
b=1:10
...
j=1:5
vect=[]
I can use for a =1:10
for b=1:10
...
vect = [vect;a.b...j]
end
end
but it looks not elegant. Is there a better way to generate it?

Image Analyst on 19 Jan 2020
So do you not want [a b c d e f g h i j] like you said, with a being a 10 element vector, b being another vector etc. (I gave my answer below assuming that.) David is assuming that a is really one element of your "a" (not the whole vector) and takes on every value in that a, so basically you have every possible permutation of all a values, etc.?
saihua lin on 19 Jan 2020
Thanks David. My question is a general question and no specific application. I can reduce it to [a b c d] for example.
a=1:10
b=1:10
c=1:3
d=1:5
Total array size is 10*10*3*5. So Yes, I'd like to have possible permutation. I can use for commands but it will need several for. If there're other more compact ways to generate these vectors, that would be good.
Stephen Cobeldick on 19 Jan 2020
"I'd like to have possible permutation"

Walter Roberson on 19 Jan 2020
a=1:10;
b=1:10;
c=1:3;
d=1:5;
[A, B, C, D] = ndgrid(uint8(a), uint8(b), uint8(c), uint8(d)) ;
v = [A(:), B(:), C(:), D(:)] ;

Image Analyst on 19 Jan 2020
Try
a = 1 : 10
b = 1 : 10
...
j = 1 : 5
outputVector = [a, b, c, d, e, f, g, h, i, j]