Page 86 - Basics of MATLAB and Beyond
P. 86
subplot(221)
spy(A)
subplot(222)
gplot(A,[x y])
axis equal off
for i = 1:10
text(x(i),y(i),int2str(i))
end
The plots show the sparse node-connection matrix on the left and the
physical connection on the right.
Exercise 7 Repeat this communications example for the case of
100 nodes around the circle. Then try changing the connection
matrix. (Answer on page 187.)
26 Text Strings
A string is an array of characters. For example, these are strings:
’hello’, ’John Smith’, and ’12’. The last one is a string, not the
number 12, because it is surrounded by quotes. matlab represents char-
acters as their ascii values. You can convert between ascii values and
the characters they represent using the double and char commands:
>> alph = ’ABCDE’
alph =
ABCDE
>> num = double(alph)
num =
65 66 67 68 69
>> char(num)
ans =
ABCDE
>> char(num+5)
ans =
FGHIJ
The double command converts its argument to double precision values,
the default matlab format.
To get a quote character in a string use two quotes in succession:
>> str = ’you’’re the one’
c 2000 by CRC Press LLC
