Introduction to MATLAB - Numerical Methods in Engineering with MATLAB - page 22

linspace
Anothermeansofcreating an array with equally spaced elements is the linspace
function. The statement

x = linspace( xfirst , xlast , n )

creates an array of n elements starting with xfirst and ending with xlast . Here is an
illustration:

>>x=linspace(0,1,5)
x=

0 0.2500 0.5000 0.7500 1.0000

logspace
The function logspace is the logarithmiccounterpartof linspace . The call

x = logspace( zfirst , zlast , n )

10 z first and ending with

creates n logarithmically spaced elements starting with x =

10 z last . Here is an example: x =

>>x=logspace(0,1,5)
x=

1.0000 1.7783 3.1623 5.6234 10.0000

zeros
The function call

X = zeros( m n )

,

returns amatrix of m rows and n columnsthat is filledwith zeroes.When the fun-
ctioniscalledwith a single argument, e.g., zeros( n ) , a n × n matrix iscreated.

ones

X = ones( m , n )

The function ones works in the manneras zeros , but fills the matrix with ones.

rand

X = rand( m , n )

Thisfunctionreturns amatrix filledwith random numbers between 0 and 1.