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Messages 2024 - 2053 of 4044   Oldest  |  < Older  |  Newer >  |  Newest
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2024
Hi Adrian, Kelvin's conjecture uses volume squared divided by surface cubed. http://mathworld.wolfram.com/KelvinsConjecture.html off_report gives this ratio....
vortexswirling
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Oct 1, 2008
4:18 pm
2025
Hi Roger ... It sounds right. The conjecture is looking for a minimal surface area for a given volume and so the aim is for V^2/S^3 to be as high as possible. ...
Adrian Rossiter
adrianrossiter
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Oct 1, 2008
5:45 pm
2026
Hi Roger ... I was just closing the MathWorld page when I noticed that it described Kelvin's curved truncated octahedron as less optimal than the plane faced...
Adrian Rossiter
adrianrossiter
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Oct 1, 2008
5:55 pm
2027
Hi Adrian, ... I was thinking backwards. As it mentions later on the page the WP foam beats that number and it is a higher number. The number they give...
vortexswirling
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Oct 1, 2008
6:27 pm
2028
Hi Roger ... off_report just gives the bare ratio whereas the MathWorld figure is for the isoperimetric quotient, which is 36*PI times greater 0.0066612233 *...
Adrian Rossiter
adrianrossiter
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Oct 2, 2008
8:19 am
2029
Hi Adrian, ... Fumbling about in a spreadsheet I determined the reason for using 36*pi is because for a sphere (V^2/S^3)*36*PI = 1 There rounder the polyhedron...
vortexswirling
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Oct 2, 2008
1:51 pm
2030
I just found in my notes that a = 3 * 2^(2/3) is the cube root of 108. But simply cubing "a" doesn't seem to be enough. I think the components of each formula...
vortexswirling
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Oct 2, 2008
7:22 pm
2031
... I seem to be repeating something I tried last year! I found this discussion between myself and Guy, June of 2007. It may be that there cannot be integer...
vortexswirling
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Oct 2, 2008
7:42 pm
2032
Hi Carmen ... You could calculate the lengths and angles with the Antiprism programs. http://www.antiprism.com/ Here is an example showing how you would do it....
Adrian Rossiter
adrianrossiter
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Oct 3, 2008
2:20 pm
2033
Hi Roger ... An example of a rational volume from irrational coordinates is a unit cube where you slide the vertices of the top square by sqrt(2) to the right....
Adrian Rossiter
adrianrossiter
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Oct 3, 2008
2:29 pm
2034
Hi Adrian, ... I just noticed today that the off_trans -T command of this new off_trans doesn't change the output. I found out why. The new centre variable is...
vortexswirling
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Oct 3, 2008
2:56 pm
2035
Hi Roger ... It defaults to false here. The problem must have been a bit puzzling! I will add in your change. Adrian. -- Adrian Rossiter adrian@... ...
Adrian Rossiter
adrianrossiter
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Oct 3, 2008
3:16 pm
2036
Hi Adrian, I decided to test the inside/outside code as the stub of a new program. I was worried about what would happen if the beginning of each face list...
vortexswirling
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Oct 3, 2008
3:56 pm
2037
Hi Roger ... Good! ... It will be interesting to see. I haven't given it much thought but I imagine that constructing the algorithm to identify the parts from...
Adrian Rossiter
adrianrossiter
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Oct 4, 2008
2:56 pm
2038
Hi Adrian, ... the ... I have to admit I just don't get normals. ... I had thought that if one identified interior and exterior vertices, it would follow that...
vortexswirling
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Oct 4, 2008
10:00 pm
2039
Hi Roger ... The test looks like you could find the line of intersection of two face planes and then see if it intersects the edges (line segments) of either...
Adrian Rossiter
adrianrossiter
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Oct 5, 2008
9:39 am
2040
Hi Adrian, ... Looking at the example, I don't see anywhere that these two are not the same segments. You also mentioned about edge intersection. There could...
vortexswirling
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Oct 5, 2008
3:05 pm
2041
Hi Roger ... Whoops, I thought you were describing the tetrahedron vertices poking through the cube so I didn't run your commands! Here is an image using your...
Adrian Rossiter
adrianrossiter
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Oct 5, 2008
6:00 pm
2042
Hi Adrian, ... Talk about rising complexity! ... I had thought bow-ties could be pre-processed into individual convex polygons. This has serious problems...
vortexswirling
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Oct 6, 2008
2:15 pm
2043
Hi All, http://www.interocitors.com/tmp/bravais.rc1.zip I put up a new bravais program. There have been extensive changes. I have placed a line at the top of...
vortexswirling
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Oct 6, 2008
5:09 pm
2044
Roger, looking forward to testing out your new bravais with some bells and whistles. when I run it, I tried -h and got the help list without any -L option for...
stevewaterman51
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Oct 7, 2008
12:22 pm
2045
Hi Steve, ... I double checked the zip file and it has the RC1 version. However, there the -L options wasn't working as documented so I fixed it. (see below)...
vortexswirling
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Oct 7, 2008
1:15 pm
2046
Roger, Okay...the new bravais worked when i out it in the......bin I got the help with -L and got the other coding to work as well, and the "radial sweep...
stevewaterman51
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Oct 7, 2008
1:55 pm
2047
Hi Roger ... I think sorting out the faces one at a time sounds good too. ... The situation doesn't seem too bad. After calculating the segments of...
Adrian Rossiter
adrianrossiter
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Oct 7, 2008
2:26 pm
2048
Hi Steve, ... exploration. Well, I didn't explain why the -G 8 option completely. As the help says: -G <type> automatic grid center type (type 8 invalid for...
vortexswirling
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Oct 7, 2008
3:39 pm
2049
Roger. Loving what i see so far...the squared distance..in order and the occurences...great stuff. ... YES YES...the yin yang of these two unit cells....nicely...
stevewaterman51
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Oct 7, 2008
4:52 pm
2050
Roger, cell sub-division algorithm.... 1 take any unit cell and place a cloned copy at each of its vertex. 2 remove whatever is outside the original unit cell....
stevewaterman51
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Oct 7, 2008
5:09 pm
2051
Hi Adrian, ... circuits. ... I'm not quite following this. Indeed, doing this with trees is the way to do this. It is a bit like following maze paths. I think...
vortexswirling
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Oct 7, 2008
5:55 pm
2052
Hi Steve, ... For simple lattices (ex. cubic P, monoclinic P etc) the -G options already can do this. -G p (for corner) would have the vertex at the centroid...
vortexswirling
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Oct 7, 2008
6:12 pm
2053
Roger, ... say its a 7x7x7 in the text antiview had it as an 8x8x8 steve...
stevewaterman51
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Oct 7, 2008
6:52 pm
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