linbox

example of a blackbox that is space efficient, though not time efficient. More...
#include <jitmatrix.h>
Public Member Functions  
JIT_Matrix (const _Field &F, const size_t m, const size_t n, const JIT_EntryGenerator &JIT)  
m by n matrix is constructed. More...  
example of a blackbox that is space efficient, though not time efficient.
just in time matrix.
the matrix itself is not stored in memory. rather, an entrygenerator function is called to provide the entries. the entry generator is called once for each entry during an apply or applytranspose operation.
An toy example of its use is the Hilbert matrix, whose entry is generated by the formula in zero based indexing. The motivating examples were matrices also defined by formula, the Paley type matrices.
_Field  only need provide the init() and axpyin() functions. 
JIT_EntryGenerator  gen() is a function object defining the matrix by providing gen(e, i, j) which sets field element e to the i ,j entry of the matrix. Indexing is zero based. 

inline 
m by n matrix is constructed.
JIT(Field::Element& e, size_t i, size_t j) is a function object which assigns the i,j entry to e (and returns a reference to e) and must be valid for 0 <= i < m, 0 <= j < n.