Hello Luc and Ted, Thanks for your comments, see my answers below.
-----Message d'origine----- De : Luc Maisonobe [mailto:luc.maison...@free.fr] Envoyé : mercredi 27 juillet 2011 09:02 À : Commons Developers List Objet : Re: [math] Adding a new class to handle Matrix with 3 columns/rows Le 26/07/2011 17:59, Tanguy Yannick a écrit : >> Hello, >> >> In project SIRIUS (CNES), we have some need for a Matrix33 (3 columns, >> 3 >> rows) object. It is very common to use this kind of matrix to apply >> rotation to a position vector (vector3D). >> >> The incompatibility between the Vector3D of geometry package and the >> matrix/vectors of the linear package is a lack that we propose to fill >> by creating a "Matrix33" in the geometry.threed package. >Looks finie to me. >> This new matrix will only propose basic methods, optimized for this >> size of matrix : add, substract, product (Vector3D or Matrix33), >> transpose, determinant, isSymmetric .. >Do you intend to provide solvers too ? For such small size matrices, with an >explicit dimension, it could even be done >>using inlined Cramer method. No, we don't need solvers. >> We will also propose some new constructors to build gaps between this >> new matrix and the matrix of linear package. > Yes, having a way to change from one view to the other is a clear need. Yes, we prefer to add a constructor from Array2DRowRealMatrix and a getter (that returns a Array2DRowRealMatrix) than to implement the whole interface RealMatrix (or inherit the AbstractMatrix). If some users want to do some complex calculation with a 3x3 Matrix, they can use that getter. Best regards, Yannick >> >> Thanks for your advice about this feature. >As per all contributions you may propose, be aware of the Apache >Software Foundation motto you will see at the beginning of the >foundation home page: "We consider ourselves not simply a group of >projects sharing a server, but rather a community of developers and users." >We are happy to get contributions, but only as long as they come with >some involvement and willingness to maintain them. Of course, very small >contributions can be dealt with by the existing community, but we simply >don't have the resources to maintain large contributions we didn't wrote >and which are dumped at us. >best regards, >Luc > > Yannick TANGUY > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org > For additional commands, e-mail: dev-h...@commons.apache.org > > --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: dev-unsubscr...@commons.apache.org For additional commands, e-mail: dev-h...@commons.apache.org
