Preface

This document describes the use of a suite of routines which enable finite element data to be entered into the FEMVIEW database. These routines are compatible with FEMGV User Manual and Fortran 77.

These Database Interface Routines may be incorporated into Translator programs to enable data to be entered into the FEMVIEW database without the necessity of executing the FEMGV program. This approach is faster and more convenient, and will reduce the number of permanent copies of a particular block of data.

It is theoretically possible to go a step further, and to incorporate the Database Interface Routines into the finite element analysis software itself.

The Database Interface Routines enter model data into the FEMVIEW database one data set at a time; a data set being nodal co-ordinates or element-wise results for example. This is done by writing each data set to a temporary binary file, checking for errors in the data, and then copying the data set from the temporary file into the FEMVIEW database. The temporary file is then rewound and is ready for the next data set to be processed.

The maximum size of the temporary file will be determined by the size of the largest data set only, and not by the size of the whole model. The Database Interface Routines perform all error checking for each data set as it is written to the temporary file. Thus if an error is detected, appropriate action may be taken before the data set is entered into the database.

These routines may be used in conjunction with up to 10 temporary files simultaneously, offering a degree of parallel processing. The structure of a particular analysis package output file will govern whether this facility may be usefully employed. A common example might be an output file in which element-wise results at Gauss points have been extrapolated to the element nodes, and both sets of results are given for each element.

Error recovery is provided within these routines, the severity of the error governing the action which can be taken. The routines offer three options for error recovery; the user may attempt to correct the error and enter the data into the temporary file again, abandon the current data set and continue with further data sets, or the user may abandon input for the whole model.

It is only possible to enter data directly into the FEMVIEW database if the database resides on the same machine as the analysis program. The Database Interface Routines may still be used when the FEMVIEW database and analysis program reside on different machines, but in this case the routines must be used to write data to a neutral character file instead of directly to the FEMVIEW database. The neutral character file may then be transferred to the machine upon which the database resides, and entered into the database using the FEMGV program. A third option is provided which enables data to be processed into the database and simultaneously out to a neutral character file.

It is assumed that the users of these routines have access to the FEMGV Version 6 User Manual and that they have had some experience of the program. The reader should refer to Appendices B of the FEMGV User Manual.