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<DIV><FONT face=Arial size=2>Greetings All!</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Got some weird results when I attempted to contruct
a torus by rotation of a disk; it appears </FONT></DIV>
<DIV><FONT face=Arial size=2>one cannot extrude a surface beyond an angle of Pi.
Is this a bug, or a feature?</FONT></DIV>
<DIV><FONT face=Arial size=2>See the program, 'torus.geo', listed
below</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Best Regards</FONT></DIV>
<DIV><FONT face=Arial size=2>Layne L. Wright</FONT></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV><FONT face=Arial
size=2>/*********************************************************************
<BR> *<BR> * Torus.geo Gmsh Program to Construct a
Torus<BR> *<BR> *********************************************************************/</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>cm =
1e-02; // Define our
scale<BR>Lc1 = 0.5 * cm; // Mesh
size<BR>r1 = 4 * cm; //
Origin->Disk center radius<BR>r2 = 1 *
cm; // Disk radius</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>r2c = r2 * Cos( Pi/4 ); // Cos/Sine terms to
define disk circumference points<BR>r2s = r2 * Sin( Pi/4 );</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>deg90 = Pi /
2; // Radian
representation of 90 Degs</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Point(1) = { 0.0, 0.0, 0.0,
Lc1 }; // Origin</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Point(2) = { 0.0, r1
, 0.0 , Lc1 }; // Circle center<BR>Point(3) = {
0.0, r1+r2 , 0.0 , Lc1 }; // 8 points along the
circumference<BR>Point(4) = { 0.0, r1+r2c, r2s , Lc1
};<BR>Point(5) = { 0.0, r1 , r2
, Lc1 };<BR>Point(6) = { 0.0, r1-r2c, r2s , Lc1
};<BR>Point(7) = { 0.0, r1-r2 , 0.0 , Lc1
};<BR>Point(8) = { 0.0, r1-r2c, -r2s, Lc1
};<BR>Point(9) = { 0.0, r1 , -r2 , Lc1
};<BR>Point(10) = { 0.0, r1+r2c, -r2s, Lc1 };</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>Circle(1) = { 3, 2, 4 } ;
// Arcsegments along the circumference<BR>Circle(2) = { 4, 2, 5 }
;<BR>Circle(3) = { 5, 2, 6 } ;<BR>Circle(4) = { 6, 2, 7
} ;<BR>Circle(5) = { 7, 2, 8 } ;<BR>Circle(6) = { 8, 2,
9 } ;<BR>Circle(7) = { 9, 2, 10 } ;<BR>Circle(8) = { 10, 2, 3 }
;</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>// Merge arcsegments into a disk <BR>Line Loop (9)
= { 1,2,3,4,5,6,7,8 };<BR>Plane Surface(10) = {9};</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>// Extrude the disk to form a partial
torus</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>// Things are fine as long as extrusion angle is
<= Pi<BR>/* Extrude Surface {10, {0,0,1}, {0,0,0}, 1* deg90 };
*/</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>// Things get somewhat odd for angles >
Pi<BR>Extrude Surface {10, {0,0,1}, {0,0,0}, 3* deg90
};</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>// Volume assigment done interactively in
'Gmsh'<BR>Surface Loop(53) = {10,23,27,31,35,39,43,47,51,52};<BR>Volume(54) =
{53};<BR>Physical Volume(55) = {54};</FONT></DIV>
<DIV> </DIV>
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