MATLAB Programming

1 Data Structures
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1
Single-Colon Indexing with Different Array Types. When you index
into a standard MATLAB array using a single colon, MATLAB returns a
column vector (see variable n, below). When you index into a structure or cell
array using a single colon, you get a comma-separated list “Comma-Separated
Lists” on page 3-80 (see variables c and s, below).
Create three types of arrays:
n = [1 2 3; 4 5 6];
c = {1 2; 3 4};
s = cell2struct(c, {'a', 'b'}, 1);
s(:,2)=s(:,1);
Use single-colon indexing on each:
n(:) c{:} s(:).a
ans = ans = ans =
1 1 1
4 ans = ans =
2 3 2
5 ans = ans =
3 2 1
6 ans = ans =
4 2
Using a Matrix As an Index
You can repeatedly access an array element using the ones function. To create
a new 2-by-6 matrix out of the ninth element of a 4-by-4 magic square A,
B = A(9 * ones(2, 6))
B =
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