The Implicitly Restarted Arnoldi Method in ARPACK 44 .. In addition to this user ‘s guide, complete documentation of usage, data re-. Introduction. ARPACK is a collection of Fortran77 subroutines designed to solve large scale eigenvalue problems. About. ARPACK is a collection of Fortran77 subroutines designed to solve large- scale eigenvalue problems. Versions and Availability. ▷ Display Softenv Keys.

Author: | Akitaxe Akisho |

Country: | Morocco |

Language: | English (Spanish) |

Genre: | Video |

Published (Last): | 8 May 2011 |

Pages: | 71 |

PDF File Size: | 4.53 Mb |

ePub File Size: | 1.66 Mb |

ISBN: | 789-1-62644-464-8 |

Downloads: | 39335 |

Price: | Free* [*Free Regsitration Required] |

Uploader: | Meztikus |

The list will look something like: For best results, the data type of M should be the same as that of A. This file contains module commands doxumentation set up the initial shell environment. This argument applies only for real-valued A and sigma!

This is done internally via a sparse LU decomposition for an explicit matrix M, or via an iterative solver for a general linear operator. H, depending on which one is more efficient. documsntation

The command softenv will provide a list of available packages. The user just has to adapt his program by replacing these names by his own ones. Viewing Available Packages The command softenv will provide a list of available packages.

When a user logs in, the system looks for a file named. Modules Modules is a utility which helps users manage the complex business of setting up their shell environment in the face of potentially conflicting application versions and libraries. Which k eigenvectors and eigenvalues to find:.

Documentatoon bukling mode, the real symmetric matrix A is required to be positive semi-definite while B is only required to be real symmetric indefinite. The currently converged eigenvalues and eigenvectors can be found as eigenvalues and eigenvectors attributes of the exception object. SoftEnv is a utility that is supposed to help users manage arapck user environments with potentially conflicting application versions and libraries.

This can be achieved in the following way: See ddocumentation for more information. Module is currently available only on SuperMIC.

## Introduction

Find k eigenvalues and eigenvectors of the real symmetric square matrix or complex hermitian matrix A. If small eigenvalues are desired, consider using shift-invert mode for better performance.

For the same reason, the SetXXXMode functions, which are intended to define the problem starting from an object built by the default constructor, should not be used in this context. The functions ChangeMultBx and ChangeMultOPx should not be used either since the matrix-vector product functions are provided by the interface object.

It is handy to test out individual keys, but can lead to trouble if changing multiple keys. M must represent a real, symmetric matrix if A is real, and must represent a complex, hermitian matrix if A is complex.

If A is complex, the matrix B is required to be hermitian positive semi-definite, except in regular mode where it should be positive definite.

Softenv SoftEnv is a utility that is supposed to help users manage complex user environments with potentially conflicting application versions and libraries.

Thus, in our program, once matrices AB and vector u have been defined see Remark 1and assuming A is real symmetric positive semi-definite and B is symmetric, we’ll have to write something like the following: Modules is a utility which helps users manage the complex business of setting up their shell environment in the face of potentially conflicting application versions and libraries.

It takes the form: Describe listed modules The -h option to module will list all available commands. Find eigenvalues near sigma using shift-invert mode. The hierarchy of the classes is the following: GetN -1 ; ArProb.

Notice that B may still be real and symmetric. Specify strategy docukentation use for shift-invert mode. The modes are as follows:. Managing Modules Besides availthere are other basic module commands to use for manipulating the environment.

For instance, ff one wants to add the Amber Molecular Dynamics package into their environment, the end of the. The listing will look something like:. If A is real, the matrix B is required to be real symmetric positive semi-definite, except in regular mode where it should be positive definite. Besides availthere are other basic module commands to use for manipulating the environment.

### ARPACK-NG – Documentation

See also the warning written in the previous section Warning. For the computation of the eigenvalues, it is only used to carry the numbering structure of the unknowns. If sigma is None, M is positive definite If sigma is specified, M is positive semi-definite.

It is typically the right-hand side vector but it may be any vector term compatible with the problem and defined on the same domain. Details about each shell follows.

The listing will look something like: The vector u is a vector associated to the problem. The member function GetN is better to be used to determine the dimension of the problem.

## Navigation and service

Starting vector for iteration, of length min A. Default Setup When a user logs in, the system looks for a file named. This class is an abstract base class so that the classes to be used in the program are the classes that are derived from this one see 2. In the documentation, the description of the constructor in shift and invert and buckling modes is: