Programming and Graphics

350 Introduction to C++ Programming and Graphics

• Matrix definition, addition, and multiplication:

>>a=[12;34]

a=

12

34

>>b=[[12]’[24]’]

b=

12

24

>> a+b

ans =

24

58

>> c = a*b

c=

510

11 22

• Multiply a complex matrix by a complex vector:

>> a = [1+2i 2+3i; -1-i 1+i]

a=

1.0000 + 2.0000i 2.0000 + 3.0000i

-1.0000 - 1.0000i 1.0000 + 1.0000i

>> v = [1+i 1-i]

v=

1.0000 + 1.0000i 1.0000 - 1.0000i

>> c = a*v’

c=

2.0000 + 6.0000i

-2.0000 + 2.0000i

By taking its transpose indicated by a prime, the row vector,v, becomes a
column vector that is conformable with the square matrix,a.

• Printπ:

>> format long

>> pi

ans =

3.14159265358979