Vector Operations in Octave

Multivariate Statistical Techniques
Vector Operations in Octave

What is Octave?

Octave is an open source program that performs vector and matrix operations. It is interoperable with another matrix program called MatLab, that is, the commands in Octave and MatLab are the same or very similar.

There are versions of Octave for Windows, Mac OS X, and Linux. It can be freely downloaded over the Internet from a number of diffent sites depending on your operating system.

What is the downside of Octave?

Octave is a complex program made up of a large number of components. This fact can make the program difficult and time consuming to install. On the Mac, Octave runs from the unix monitor, it is not an Aqua program.

The Vector

octave: v = [3;2;2]
v =

  3
  2
  2
 
octave: v
v =
 
  3
  2
  2

"Transpose" of a Vector

octave: v'
ans =

  3  2  2

Adding Vectors

octave: w = [4;1;2]
w =

  4
  1
  2

octave: v+w
ans =

  7
  3
  4

Subtracting Vectors

octave: v-w
ans =

  -1
   1
   0

Multiplication by a Scalar

octave: c = 3
c = 3

octave: c*v
ans =

  9
  6
  6

octave: c*w
ans =

  12
   3
   6

Vector Dot Product

octave: dot(v,w)
ans = 18
 
octave: dot(w,v)
ans = 18
 
octave: dot(v,v)
ans = 17
 
octave: dot(w,w)
ans = 21

Length of a Vector

octave: a = [4;3]
a =

  4
  3

octave: norm(a)
ans = 5
 
octave: v
v =
 
  3
  2
  2
 
octave: norm(v)
ans = 4.1231
 
octave: w
w =

  4
  1
  2

octave: norm(w)
ans = 4.5826

Unit Length Vector

octave: l = [1/2;1/2;1/2;1/2]
l =

  0.50000
  0.50000
  0.50000
  0.50000
 
octave: norm(l)
ans = 1

The Unit Vector

octave: u = [1;1;1]
u =
 
  1
  1
  1
 
octave: dot(u,u)
ans = 3
 
octave: v
v =
 
  3
  2
  2
 
octave: dot(u,v)
ans = 7
 
octave: w
w =
 
  4
  1
  2
  
octave: dot(u,w)
ans = 7

Multivariate Course Page

Phil Ender, 22oct03

Multivariate Statistical Techniques Vector Operations in Octave