Re: [eigen] [PATCH] Toeplitz matrix specialization |

[ Thread Index | Date Index | More lists.tuxfamily.org/eigen Archives ]

*To*: eigen@xxxxxxxxxxxxxxxxxxx*Subject*: Re: [eigen] [PATCH] Toeplitz matrix specialization*From*: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>*Date*: Thu, 29 Jan 2009 22:00:26 +0100*Dkim-signature*: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type :content-transfer-encoding; bh=ukiiJkgtkEOp0HLhoqXOhnmE6G3aoc8LksTnxWkzVYE=; b=XGWtUGRgC4J/JrflFiWeK2PZ3ChgGvvwpG2NVN5Zuql2Ig9IhI6RccIZUd2uZ0EjcM dw1GttYuOJ7Gcwh3VhWrCk062Wi8FlG7epahjhbjG3cStPLh1lNM80q8/ZfOyYK4gSsn STaaYF9016rrEtnU9KNdJr2DiGanN1Scq4XQk=*Domainkey-signature*: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type:content-transfer-encoding; b=aD9FFQewXcLvFLfbQv7BWQhXMy7ivyrIWkjwL9AuT4MPUFphauCqZRAJ5t4XjfMJ/f 9+jLOuId1kXPyjbdNWEP+1TMYEPRITG6WgdAi4fOEEZg3Wbr/1juHZ6GREdU+fG+Vcz9 5Q4F+lf6M4SgBoHajiNed8xj1/yeGtjZdwtbo=

2009/1/29 Keir Mierle <mierle@xxxxxxxxx>: > On Thu, Jan 29, 2009 at 11:36 AM, Gael Guennebaud > <gael.guennebaud@xxxxxxxxx> wrote: >> On Thu, Jan 29, 2009 at 7:55 PM, Keir Mierle <mierle@xxxxxxxxx> wrote: >>> On Thu, Jan 29, 2009 at 6:40 AM, Gael Guennebaud >>> <gael.guennebaud@xxxxxxxxx> wrote: >>>> Hi, >>>> >>>> to start the debate I put some thougths on the wiki: >>>> http://eigen.tuxfamily.org/index.php?title=SpecialMatrix >>> >>> The idea of making solveTriangular into Part::solve() sounds good to >>> me. Right now the hetergeneous API for solving triangular systems is >>> unfortunate. I vote to have solve() work as expected for triangular >>> matrices with the same API as LU::solve, SVD::solve, QR::solve, etc >>> (i.e. MyVec x; bool succeeded = my_triangular_mat.solve(b, &x);). >>> Perhaps mymat.upperTriangular().solve(...)? >> >> yes, exactly. >> >>> Is there an excessive runtime cost to detecting a singular matrix in >>> the triangular solver? >> >> N comparisons, just like for Cholesky. > > Is it possible to have a bit to mark the martix as invertible by the > user, to avoid the runtime cost? I.e. so that the check is optimized > away when the bit is set. However, we should benchmark the cost of > having the check to make sure it's high enough to want to remove. +1 We already have bits (which we control by calling matrix.marked<someBit>()) for triangularness, unit-diagonal, zero-diagonal, so why not one more bit, and I know I have a use case in the LU solver where I can guarantee that my triangular expression is invertible. Cheers, Benoit

**References**:**[eigen] [PATCH] Toeplitz matrix specialization***From:*Ricard Marxer Piñón

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Benoit Jacob

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Mauro Iazzi

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Benoit Jacob

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Gael Guennebaud

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Keir Mierle

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Gael Guennebaud

**Re: [eigen] [PATCH] Toeplitz matrix specialization***From:*Keir Mierle

**Messages sorted by:**[ date | thread ]- Prev by Date:
**Re: [eigen] [PATCH] Toeplitz matrix specialization** - Next by Date:
**Re: [eigen] Totally missing /O2 for MSVC-Compiler** - Previous by thread:
**Re: [eigen] [PATCH] Toeplitz matrix specialization** - Next by thread:
**Re: [eigen] [PATCH] Toeplitz matrix specialization**

Mail converted by MHonArc 2.6.19+ | http://listengine.tuxfamily.org/ |