Description of copy

copy		Programmers Guide
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Category:algorithms

Component type:function

Prototype

template <class LinalgA, class LinalgB> void copy(const LinalgA& A, LinalgB B) ;

Description

Copy the elements of matrix A into matrix B, or copy the elements of vector x into vector y. For shaped and sparse matrices, this copies only the elements stored in A to B. If x is a sparse vector and y is dense, a "scatter" is performed. If y is sparse and x is dense, then a "gather" is performed. If both vectors are sparse, but of different structure the result is undefined.

Definition

mtl.h

Preconditions

Complexity

O(m*n) for matrices. O(nnz) if either A or B are sparse and of the same orientation (otherwise it can be O(nnz^2). O(n) for vectors.

Example

In vecvec_copy.cc:

  dense1D<double> x(10,1);
  dense1D<double> y(10);
  double alpha = 4.0;
  mtl::copy(scaled(x, alpha), y);

Notes

See also