Graphics Programs Reference
In-Depth Information
>> a = zeros(2,3)
a=
0
0
0
0
0
0
>> b = ones(2,2)/2
b=
0.5000
0.5000
0.5000
0.5000
>> u = rand(1,5)
u=
0.9218
0.7382
0.1763
0.4057
0.9355
>> n = randn(5,5)
n=
-0.4326
1.1909
-0.1867
0.1139
0.2944
-1.6656
1.1892
0.7258
1.0668
-1.3362
0.1253
-0.0376
-0.5883
0.0593
0.7143
0.2877
0.3273
2.1832
-0.0956
1.6236
-1.1465
0.1746
-0.1364
-0.8323
-0.6918
>> eye(3)
ans =
1
0
0
0
1
0
0
0
1
3.4 Subscripting
Individual elements in a matrix are denoted by a row index and a column
index. To pick out the third element of the vector
u
type:
>> u(3)
ans =
0.1763
You can use the vector
[123]
as an index to
u
. To pick the first three
elements of
u
type
>> u([1 2 3])
ans =
0.9218
0.7382
0.1763
Remembering what the colon operator does, you can abbreviate this to
