From 7e3bcaff834af7eabf368b1912d24167034446c8 Mon Sep 17 00:00:00 2001 From: Andrea Franceschini Date: Tue, 19 Mar 2024 14:00:48 +0100 Subject: [PATCH] Updating README.md --- README.md | 93 +++++++++++++++++++++++++++------------- examples/lapl/config.xml | 7 +-- examples/mech/config.xml | 11 ++--- 3 files changed, 69 insertions(+), 42 deletions(-) diff --git a/README.md b/README.md index 225f242..067c02d 100644 --- a/README.md +++ b/README.md @@ -61,36 +61,69 @@ Giambellino 7, 35129 Padova, Italy); at [University of Padova](https://www.unipd.it/en). ## Parameters ## -The parameters needed to set-up the AMG preconditioner in ChronosLab are the following: - -* **problem type** can be either **mech** or **lapl** and denotes the origin of the linear - system at hand. The first one sets the default for mechanical problems, the second one - for system arising from the discretization of Laplace equations. -* **tspace_ntv** is the number of test vector (approximation of the near kernel) of the problem - at hand. In general the size of the test space equals the size of the test space that is - given as input but can be overwritten by the user through **tspace_ntv**. If there is no - test space as input, the default value is 1. -* **tspace_iter** is the number of iterations of SRQCG (Simultaneous minimization of - the Rayleight Quotient though CG). By default the number of iterations is 0. -* **smooth_type** defines the type of smoother that is used. Possible values are **jacobi**, - **ligthFSAI**, **mediumFSAI**, **heavyFSAI** and **nestFSAI**. The first one is the simple - Jacobi preconditioner. Those from light to heavy denote different FSAI set-up from the - cheapest and less accurate to the more expensive and more accurate. The last one denotes - a novel type to compute FSAI that is recommended for highly ill-conditioned problems. -* **coars_tau** is the strength of connection threshold that is used for coarsening. In case - of **mech** problems, the symmetric strength of connection is used with default 0.01. - In case of **lapl** problems, the classical strength of connection is used with default - 0.25. -* **prolo_smooth** is a parameter used only for **mech** problems and can take value **none** - if the prolongation is not improved by smoothing, **smooth** if the prolongation is smoothed - and **emin** if the prolongation is improved by energy minimization. The default value is - **emin** - -There are other parameters in ChronosLab that an advanced user can access to better tune -the AMG set-up on the problem at hand. These parameters and their meaning can be found by -inspecting the main driver in each folder (e.g. coarsen.m in the folder coarsen, tspace.m -in the folder tspace, etc.). Moreover the FSAI smoother can be also used as stand-alone -preconditioner. +The parameters needed to set-up the AMG preconditioner in ChronosLab are the +following: + +* **problem type** can be either **mech** or **lapl** and denotes the origin of + the linear system at hand. The first one sets the default for mechanical + problems, the second one for system arising from the discretization of + Laplace equations. +* **tspace_ntv** is the number of test vector (approximation of the near + kernel) of the problem at hand. In general the size of the test space equals + the size of the test space that is given as input but can be overwritten by + the user through **tspace_ntv**. If there is no test space as input, the + default value is 1. +* **tspace_iter** is the number of iterations of SRQCG (Simultaneous + minimization of the Rayleight Quotient though CG). By default the number of + iterations is 0. +* **smooth_type** defines the type of smoother that is used. Possible values + are **jacobi**, **ligthFSAI**, **mediumFSAI**, **heavyFSAI** and + **nestFSAI**. The first one is the simple Jacobi preconditioner. Those from + light to heavy denote different FSAI set-up from the cheapest and less + accurate to the more expensive and more accurate. The last one denotes a + novel type to compute FSAI that is recommended for highly ill-conditioned + problems. +* **coars_tau** is the strength of connection threshold that is used for + coarsening. In case of **mech** problems, the symmetric strength of + connection is used with default 0.01. In case of **lapl** problems, the + classical strength of connection is used with default 0.25. +* **prolo_smooth** is a parameter used only for **mech** problems and can take + value **none** if the prolongation is not improved by smoothing, **smooth** + if the prolongation is smoothed and **emin** if the prolongation is improved + by energy minimization. The default value is **emin**. + +There are other parameters in ChronosLab that an advanced user can access to +better tune the AMG set-up on the problem at hand. These parameters and their +meaning can be found by inspecting the main driver in each folder (e.g. +coarsen.m in the folder coarsen, tspace.m in the folder tspace, etc.). Moreover +the FSAI smoother can be also used as stand-alone preconditioner. + +Here two examples of input file. The first one for a structural problem: + +```xml + + + + +``` + +while the next is for linear system arising from the Laplace equation: + +```xml + + + + +``` ## Terms of usage ## **ChronosLab** is an open source software under the MIT license and can be diff --git a/examples/lapl/config.xml b/examples/lapl/config.xml index 75fc0cb..f36a19f 100644 --- a/examples/lapl/config.xml +++ b/examples/lapl/config.xml @@ -1,11 +1,8 @@ - + diff --git a/examples/mech/config.xml b/examples/mech/config.xml index 13ab6d0..a400f13 100644 --- a/examples/mech/config.xml +++ b/examples/mech/config.xml @@ -1,13 +1,10 @@ - - - + />