Two vectors into matrix with an opeartion?

Hi everybody,

I'd like to create a matrix from 2 vectors with a subtraction.

a=[0,1,2,3]
b=[6,7,8,9]

The operation is b-a, so the resulting matrix should look like this

6   5   4   3
7   6   5   4
8   7   6   5
9   8   7   6

Additional question: Is it possible to place the results underneath the first row of Vector a

0   1   2   3
6   5   4   3
7   6   5   4
8   7   6   5
9   8   7   6

Thank you for your help in advance

Christian

Answer 1

[Alan Stevens]

Like this:

a = [0 1 2 3];
b = [6; 7; 8; 9]; % Note that b is a column vector and a is a row vector
A = repmat(a,4,1)

A =

     0     1     2     3
     0     1     2     3
     0     1     2     3
     0     1     2     3

>> m = b - A

m =

     6     5     4     3
     7     6     5     4
     8     7     6     5
     9     8     7     6

>> m = [a; m]

m =

     0     1     2     3
     6     5     4     3
     7     6     5     4
     8     7     6     5
     9     8     7     6

[madhan ravi]

using repmat() is not efficient than an implicit expansion

[Christian S.]

That was quick, wow! Thank you very much.

Very best

Christian

Answer 2

[madhan ravi]

[a; b(:) - a]