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<font face="serif">So apparently you guys can't get the diffusion
code to work using the 3D Jacobi update algorithm. Since you are
using a cube and the dx=dy=dz, you can do something like this...
which is a simple extension of equation 3.7 in your text to 3D<br>
<br>
</font><tt>scalar = diffusion_coefficient * timestep /
distance_between_blocks**2</tt><tt><br>
</tt><tt><br>
</tt><tt> do i = 1, msize</tt><tt><br>
</tt><tt> do j = 1, msize</tt><tt><br>
</tt><tt> do k = 1, msize</tt><tt><br>
</tt><tt> tempbox(k,j,i) = box(k,j,i) + &</tt><tt><br>
</tt><tt> ( ( box(k,j,i-1) + box(k,j,i+1)
- 2.0D0* box(k,j,i)) &</tt><tt><br>
</tt><tt> * mask(k,j,i-1) *
mask(k,j,i+1) + &</tt><tt><br>
</tt><tt> ( box(k,j-1,i) + box(k,j+1,i)
- 2.0D0* box(k,j,i)) &</tt><tt><br>
</tt><tt> * mask(k,j-1,i) *
mask(k,j+1,i) + &</tt><tt><br>
</tt><tt> ( box(k-1,j,i) + box(k+1,j,i)
- 2.0D0* box(k,j,i)) &</tt><tt><br>
</tt><tt> * mask(k-1,j,i) *
mask(k+1,j,i) ) &</tt><tt><br>
</tt><tt> * scalar </tt><tt><br>
</tt><tt> end do</tt><tt><br>
</tt><tt> end do</tt><tt><br>
</tt><tt> end do</tt><font face="serif"><br>
<br>
<br>
Hope that helps...<br>
<br>
<br>
</font>
<pre class="moz-signature" cols="72">--
Andrew J. Pounds, Ph.D. (<a class="moz-txt-link-abbreviated" href="mailto:pounds_aj@mercer.edu">pounds_aj@mercer.edu</a>)
Professor of Chemistry and Computer Science
Mercer University, Macon, GA 31207 (478) 301-5627
<a class="moz-txt-link-freetext" href="http://faculty.mercer.edu/pounds_aj">http://faculty.mercer.edu/pounds_aj</a>
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