These sections contain additional information as well as solutions and workarounds to problems encountered.

## 1. B2000++ Frequently Asked Questions

#### General

1.

Are there any limits in the number of degrees of freedom?

There are no a priori limits to the number of degrees of freedom other than those imposed by the 64bit address space of the CPU and the 32bit integer capacity for storing indices.

2.

Is the analysis performed in-core?

Computation of the element matrices and assembly of the non-factored matrix are performed in-core. The sparse matrix factorization can be performed out-of-core, see Sparse Linear Solvers.

3.

Is an non-symmetric and/or complex equation solver available?

Non-symmetric and complex equation solvers are available. The b2000++ program detects whether the global (stiffness) matrix is unsymmetric or complex, and automatically selects the equation solver. For an overview of the different equation solvers, see Sparse Linear Solvers.

4.

Which quasi-static nonlinear solution methods are available?

The MDL command increment_control_type allows for load-controlled, state-controlled, and continuation-type solution strategies. See MDL commands for the static nonlinear solver.

5.

Which options does B2000++ have for dynamic (transient) problems?

B2000++ contains a nonlinear transient multi-step implicit solver. See Dynamic Nonlinear Solver (B2000++ Pro).

6.

Which import filters or converters are available for B2000++?

The program b2convert_from_nas reads a Nastran® BDF file and writes an MDL file (a subset of the BDF commands is supported). The program b2convert_from_salome reads a Salome mesh and writes an MDL file.

7.

Can I export my B2000++ models and results to other formats?

There is no export facility in B2000++. However, using the Python, C/C++, or Fortran database interface, there is the possibility of writing scripts and programs which extract model and result data from a B2000++ database. Also note that the post-processor baspl++ has many advanced methods for data extraction available via its Python interface.

8.

What external formats can baspl++ read?

The graphical post-processing tool which comes with B2000++, baspl++, has specific filters to read different data formats. The data formats currently available, besides B2000++, are Tecplot, Tau, and NSMB.

9.

How do I implement a new material model in B2000++?

New material models can be programmed by means of a standard procedure.

10.

How do I implement a new element in B2000++?

New elements can be programmed by means of a standard procedure.

#### Program installation, compilation, and execution

1.

Problems with obtaining B2000++ through GIT.

1. Make sure that ssh uses protocol 2. This is done by adding the line

Protocol 2,1

in the ~/.ssh/config file. Example of a ~/.ssh/config file:

StrictHostKeyChecking no
Host *
ForwardAgent yes
ForwardX11 yes
Protocol 2,1
2. Make sure that you have an GIT account by contacting SMR.

2.

How to run a debugger with the b2000++ program.

Launch the debugger gdb:

\$ gdb /opt/smr/libexec/b2000++

When prompted, issue the run command with options, such as the B2000++ database name:

(gdb) run demo.b2m

#### B2000++ specific problems

1.

The search facility in the B2000++ on-line documentation does not find the expression "B2000++".

The search engine misinterprets the "+" character. Please omit special characters, such as "+", "-" for search expressions.