C++ for Scientists - Technische Universität Dresden

14.1. COMPUTING AN EIGENFUNCTION OF THE POISSON EQUATION 269
First, we set conceptual conditions on all arguments.
• Op is a model of BinaryFunction, i.e. the following are valid expressions for op of type Op:
– op(x,y) where x and y are instances of type X where X is a model of the concept
glas::DenseVectorCollection.
• DenseVectorCollection is a model of glas::DenseVectorCollection.
• Float is a concept of real numbers, i.e. it is float, double, or long double.
The implementation for inverse iteration could be as follows:
#ifndef athens inverse iteration hpp
#define athens inverse iteration hpp
#include
#include
namespace athens {
template
void inverse iteration( Op const& op, DenseVectorCollection& x, int m, Float& lambda ) {
glas::dense vector< typename glas::value type::type > y( glas::size(x) ) ;
x = x / norm 2( x ) ; // 2.
for ( int i=0; i