***init_dof_value

Description

This procedure imposes the initial values of specified degrees of liberty of the problem (at \(t=0\)). The values may be either uniform either defined by nset or elset or read from an initializing binary file. This file may be for example the output from a previous calculation (see the example).

Syntax

The syntax used to initialize the problem DOFs is:

***init_dof_value \(~\,~\,\) [ dof_name elset elset_name  value ] \(~\,~\,\) [ dof_name nset nset_name  value ] \(~\,~\,\) [ dof_name uniform value ] \(~\,~\,\) [ dof_name file file_name  position ]

where dof_name indicates replacement with the character name of the desired DOFs (see appendix). The keywords elset and nset indicate the type of set. These keywords require a set’s name elset_name or nset_name followed by a real value The keywords uniform and file indicate the method upon which the values will be loaded. Specifying uniform requires a real value for value which is the absolute value of the DOF. File storage set by the file keyword requires a character name for the file, file_name, and an integer value for the record position, position. The DOF values will be taken from this file position in sequence using single precision 4 byte floating point format.

Example

This example shows how to load a data file generated from a small C++ program. This source is as follows:

#include <fstream.h>
main()
{ fstream out("U2.dat",ios::out);
  float x=1.;
  for(int i=0;i<8;i++) out.write(&x,sizeof(float));
  out.close();
}

which sets a uniform value of \(1\) (for example).

The input for this example could be:

***init_dof_value
  U1 uniform 2.
  U2 file U2.dat 568

which will set all the \(u_1\) nodal displacements to \(2\), and all the \(u_2\) displacements to \(1\).