Hello! Does anyone now if there exist a function that would compute a "null space" (or "kernel" - "Ker") of a matrix and maybe also one that would compute an "image" ("Im") of a matrix. I tried R-site search and google, However I found notnihg useful! Thanks for any sugestions! I am also not sure what an "image" of a matrix is, so suggestion in this directions would also be apreciated. Ale? ?iberna
The null space or kernel of a matrix A would be the subspace of vectors v such that Av = 0. That is, it's the solution space of a homogeneous linear system of equations whose coefficients are the rows of A. R implements many ways to solve such systems. The image is the set of vectors of the form Av as v ranges over all vectors, which is the same as the span of the columns of A, aka the column space of A. You can reduce this to a basis or transform it to an orthogonal basis. Have a look at a linear algebra book to get an idea for the possibilities. Reid Huntsinger -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Ale?? ??iberna Sent: Tuesday, May 31, 2005 7:22 AM To: R-help Subject: [R] Null space (or kernel) and image of a matrix Hello! Does anyone now if there exist a function that would compute a "null space" (or "kernel" - "Ker") of a matrix and maybe also one that would compute an "image" ("Im") of a matrix. I tried R-site search and google, However I found notnihg useful! Thanks for any sugestions! I am also not sure what an "image" of a matrix is, so suggestion in this directions would also be apreciated. Ale?? ??iberna ______________________________________________ R-help at stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
davidr@rhotrading.com
2005-May-31 14:28 UTC
[R] Null space (or kernel) and image of a matrix
help.search("null space") gives Null(MASS) Null Spaces of Matrices PLEASE PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html David Reiner Rho Trading Securities, LLC -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Huntsinger, Reid Sent: Tuesday, May 31, 2005 9:02 AM To: 'Ale?? ??iberna'; R-help Subject: RE: [R] Null space (or kernel) and image of a matrix The null space or kernel of a matrix A would be the subspace of vectors v such that Av = 0. That is, it's the solution space of a homogeneous linear system of equations whose coefficients are the rows of A. R implements many ways to solve such systems. The image is the set of vectors of the form Av as v ranges over all vectors, which is the same as the span of the columns of A, aka the column space of A. You can reduce this to a basis or transform it to an orthogonal basis. Have a look at a linear algebra book to get an idea for the possibilities. Reid Huntsinger -----Original Message----- From: r-help-bounces at stat.math.ethz.ch [mailto:r-help-bounces at stat.math.ethz.ch] On Behalf Of Ale?? ??iberna Sent: Tuesday, May 31, 2005 7:22 AM To: R-help Subject: [R] Null space (or kernel) and image of a matrix Hello! Does anyone now if there exist a function that would compute a "null space" (or "kernel" - "Ker") of a matrix and maybe also one that would compute an "image" ("Im") of a matrix. I tried R-site search and google, However I found notnihg useful! Thanks for any sugestions! I am also not sure what an "image" of a matrix is, so suggestion in this directions would also be apreciated. Ale?? ??iberna ______________________________________________ R-help at stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html ______________________________________________ R-help at stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html