gridformat.html

有限元学习研究用源代码(老外的),供科研人员参考

<TITLE>IBG: How to Use IBG Grids</TITLE>

<H1>How to Use IBG Grids</H1>

 <P>You don't need the grid generator for looking at nice grids, but
for making computations on these grids. May be, you already have done
some work in this domain, in this case you already have your own data
structure for a grid. Maybe you are only starting, but even in this
case it may be useful for you to use a data structure different from
the internal IBG structure. Thus, it becomes necessary to convert the
IBG grids into your data format. There are different strategies for
using the grids created by IBG.

<H2>External Usage</H2>

 <P>This is the simplest and most safe way to use IBG grids.

 <P>Use the function <B>ibgToSimplex</B> to write the grid into a file
in the <A HREF="simplex.html">Simplex Grid Format</A> and write your
own function which is reading this format.

<H2>Internal Conversion</H2>

 <P>If you want to avoid the double conversion IBG grid -&gt; Simplex
grid -&gt; your grid, you can write an own conversion function from
the internal IBG grid to your grid format.

 <P>I recommend to use the file <A HREF="../src/ibg2simplex.c">
ibg2simplex.c</A> as a pattern. You simply have to replace the print
calls which convert the grid into the <A HREF="simplex.html">Simplex
Grid Format</A>

<H2>Using the internal IBG data structure</H2>

 <P>This strategy allows to live without conversion. But at the
current step I don't recommend it. I'm developing now a C++ version
with another internal data format which may be not compatible.

 <P>For the C++ structure I'm developing now I want to give a
guarantee that it will survive a long time, but for the current
structure there is no such guarantee.