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I have as entry a matrix which can have an several number of dimensions : n × m or n × m × p or n × m × p × q or ...
What I want to do is to access to the last dimension, something like:
data = input(:,:,1)
The problem is that the number of : can change.
952
To access elements in a multidimensional array, use integer subscripts just as you would for vectors and matrices. For example, find the 1,2,2 element of A , which is in the first row, second column, and second page of A .
N = ndims( A ) returns the number of dimensions in the array A . The number of dimensions is always greater than or equal to 2. The function ignores trailing singleton dimensions, for which size(A,dim) = 1 .
Description. sz = size( A ) returns a row vector whose elements are the lengths of the corresponding dimensions of A . For example, if A is a 3-by-4 matrix, then size(A) returns the vector [3 4] .
The end class method returns the index value for the last element of the first dimension (from which 1 is subtracted in this case). The original expression is evaluated as: A(3-1,:) For an example of an overload of end in a class that customizes indexing, see Customize Parentheses Indexing for Mapping Class.
You should make use of the fact that indices into an array can be strings containing ':':
>> data = rand(2, 2, 2, 5);
>> otherdims = repmat({':'},1,ndims(data)-1);
>> data(otherdims{:}, 1)
ans(:,:,1) =
7.819319665880019e-001 2.940663337586285e-001
1.006063223624215e-001 2.373730197055792e-001
ans(:,:,2) =
5.308722570279284e-001 4.053154198805913e-001
9.149873133941222e-002 1.048462471157565e-001
See the documentation on subsref for details.
50
It is a bit of a hack, but here is how you can do it:
data = rand(2,2,3);
eval(['data(' repmat(':,',1,ndims(data)-1) '1)'])
This will give (depending on the randon numbers):
ans =
0.19255 0.56236
0.62524 0.90487
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