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34 lines
1.2 KiB
ReStructuredText
34 lines
1.2 KiB
ReStructuredText
Why several classes ?
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=================================================================
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The library provides several interoperable forms of arrays : array, matrix and vector.
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.. note:: Why several classes ?
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Because their algebra differ, e.g. a matrix<T> is not really a array<T,2> :
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the multiplication for a matrix is the matrix multiplication, while it is element wise for the array.
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Interoperability
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---------------------------------------------------
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* These classes are largely similar, and are interoperable.
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* One can construct a matrix_view from a array, e.g. (providing the rank of the array is 2, of course...).
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* Why several classes then ? The reason is that their algebra (i.e. their behaviour under operations) differ.
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For example, a matrix<T> is not really a array<T,2> :
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the multiplication for a matrix is the matrix multiplication, while it is element wise for the array.
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The expression template implements two different algebras, one for arrays, one for matrices and vectors.
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TODO : write the example and code the make_matrix_view function....
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Example::
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array<double,3> A; matrix<double> M;
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auto res = matrix_view<double> ( A(0,range(),range()) ) + M;
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