On Mon, 26 Aug 2013 10:04:01 -0400, Konstantin Berlin wrote:
I think I like this approach a lot more.
One thing that is left out, and we discussed a lot, is the need to
support vector operations. This can also be done as an additional
interface. This is critical since it forms the basic building block
upon which all higher level matrix operations rely on. I think if we
do it right, it would allow users to implement a GPU version as well.
From usability point of view, the matrix class is kind of useless
without vector oeprations, since no important higher level operation,
other than multiplying, can be done with without copying it over to a
double array.
So maybe first we make a class
public interface RealVector extends RealMatrix
//code to implement a simple Nx1 matrix
It is quite impossible to follow you. You refer to an issue that
purports to be a starting for replacing the code currently in package
"linear" but then your use names ("RealVector", "RealMatrix") that
are defined there, and not the those from the proposal ("BasicMatrix").
Now in order not to reinvent the wheel, we will model the operations
based on the BLAS library. We can have two versions, one for the
immutable classes and another for mutable.
I think that everyone agreed that we could improve the design
(this is issue MATH-765).
But nobody seems to have really explored alternatives.
So, we rely on you to provide justification/reference about a
new design. Taking inspiration from a well-known library is
probably safe. A view on vector operations is fine of course;
but I'd need more detailed code excerpts to be able to modify
and expand what is in MATH-928.
Gilles
Then the vector operations can be expressed as in a immutable class
something like
//perform output = a*x+b*v, where x is row of current object
RealVector rowOperation(int row, double a, double b, RealVector v)
//perform output = a*x+b*v, where x is column of current object
RealVector columnOperation(int column, double a, double b, RealVector
v)
for mutable it can be basically same interface except no object is
returned
//perform output = a*x+b*v, where x is row of current object, and
puts
it in row rowResult of this matrix
void rowOperationInPlace(int row, double a, double b, RealVector v,
int rowResult)
//perform output = a*x+b*v, where x is column of current object, and
puts it in column columnResult of this matrix
void columnOperationInPlace(int column, double a, double b,
RealVector
v, int columnResult)
What do you think?
---------------------------------------------------------------------
To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org
For additional commands, e-mail: dev-h...@commons.apache.org
