# Generate n-dimensional array: problem with 1D

3 visualizzazioni (ultimi 30 giorni)
Xiaohan Du il 8 Nov 2017
Commentato: Star Strider il 8 Nov 2017
Hi all,
Imagine I'd like to generate random dimensional zeros matrix, I can do:
K>> zeros(2, 2)
ans =
0 0
0 0
K>> zeros(2, 2, 2)
ans(:,:,1) =
0 0
0 0
ans(:,:,2) =
0 0
0 0
and so on. However, for 1D case, I'll have to use:
K>> zeros(2, 1)
ans =
0
0
I cannot use zeros(2) directly, meaning I have to deal with 1D case separately. Any idea how to make it smarter?
##### 0 CommentiMostra -2 commenti meno recentiNascondi -2 commenti meno recenti

Accedi per commentare.

### Risposta accettata

Star Strider il 8 Nov 2017
That is as ‘smart’ as it gets, since it cannot read your mind. If you already have a vector and you want a zeros vector to match it, you can use the size of the original vector (or any dimension array) to create it:
x = 1:2;
v = zeros(size(x));
##### 2 CommentiMostra NessunoNascondi Nessuno
Xiaohan Du il 8 Nov 2017
For example, I know the dimension of the zeros matrix I'd create, say for 2D, it's
zeros(2, 3)
for 3D, it's
zeros(2, 3, 4)
for 4D, it's
zeros(2, 3, 4, 5)
but for 1D, if I want a 2-by-1 matrix, I cannot write
zeros(2)
because this gives me a 2-by-2 matrix. I'll have to write
zeros(2, 1)
I understand that zeros(2, 1) also exists in 2D, but it does not completely follow the rules for nD.
Star Strider il 8 Nov 2017
That is the default behaviour of the zeros function. You can always write your own single-argument function to create a column vector of zero elements:
myzeros = @(n) zeros(n,1);

Accedi per commentare.

### Categorie

Scopri di più su Creating and Concatenating Matrices in Help Center e File Exchange

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by