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Colon : | Examples See Also |
Create vectors, array subscripting, and for iterations
The colon is one of the most useful operators in MATLAB. It can create vectors, subscript arrays, and specifyfor
iterations.
The colon operator uses the following rules to create regularly spaced vectors:j:k
|
is the same as [j,j+1,...,k] |
j:k
|
is empty if j > k |
j:i:k
|
is the same as [j,j+i,j+2i, ...,k] |
j:i:k
|
is empty if i > 0 and j > k or if i < 0 and j < k |
i
,j
, and k
are all scalars.
Below are the definitions that govern the use of the colon to pick out selected rows, columns, and elements of vectors, matrices, and higher-dimensional arrays:D = 1:4results in
D = 1 2 3 4Using two colons to create a vector with arbitrary real increments between the elements,
E = 0:.1:.5results in
E = 0 0.1000 0.2000 0.3000 0.4000 0.5000The command
A(:,:,2) = pascal(3)generates a three-dimensional array whose first page is all zeros.
A(:,:,1) = 0 0 0 0 0 0 0 0 0 A(:,:,2) = 1 1 1 1 2 3 1 3 6
for
Repeat statements a specific number of times
linspace
Generate linearly spaced vectors
logspace
Generate logarithmically spaced vectors
reshape
Reshape array