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c++lapack++

How can I obtain a LaVectorDouble object which is a submatrixview of a LaGenMatDouble?

We are using Lapack++ for our matrix calculations. One of the features is the use of submatrixviews; objects that refer to the same spot in memory.

Example:

  LaGenMatDouble W = LaGenMatDouble::rand(3,4);
  LaGenMatDouble A = W(LaIndex(0,2), LaIndex(1,3));
  LaGenMatDouble b = W(LaIndex(0,2), LaIndex(0,0));

A and b are now submatrices of W.

How can I make b a LaVectorDouble to be able to perform some calculations with it?

Solution

  • The answer is to use the ref function.

    LaVectorDouble b;
b.ref(W(LaIndex(0,2), LaIndex(0,0)));

    All other functions are copying (like constructor, = and copy) or giving the wrong class (like the constructor with indices). The ref function is referencing to memory.