Acronym etidpy, J14
Name elongated trigonal dipyramid
 
 © ©
Vertex figure [33], [32,42]
General of army (is itself convex)
Colonel of regiment (is itself locally convex)
Confer
uniform relative:
tet   trip  
related Johnson solids:
etripy   tridpy  
general polytopal classes:
Johnson solids   bistratic lace towers  
External
links
wikipedia   mathworld   quickfur  

Incidence matrix according to Dynkin symbol

oxxo3oooo&#xt   → height(1,2) = height(3,4) = sqrt(3/8) = 0.612372
                 height(2,3) = 1
(pt || pseudo {3} || pseudo {3} || pt)

o...3o...    | 1 * * * | 3 0 0 0 0 | 3 0 0
.o..3.o..    | * 3 * * | 1 2 1 0 0 | 2 2 0
..o.3..o.    | * * 3 * | 0 0 1 2 1 | 0 2 2
...o3...o    | * * * 1 | 0 0 0 0 3 | 0 0 3
-------------+---------+-----------+------
oo..3oo..&#x | 1 1 0 0 | 3 * * * * | 2 0 0
.x.. ....    | 0 2 0 0 | * 3 * * * | 1 1 0
.oo.3.oo.&#x | 0 1 1 0 | * * 3 * * | 0 2 0
..x. ....    | 0 0 2 0 | * * * 3 * | 0 1 1
..oo3..oo&#x | 0 0 1 1 | * * * * 3 | 0 0 2
-------------+---------+-----------+------
ox.. ....&#x | 1 2 0 0 | 2 1 0 0 0 | 3 * *
.xx. ....&#x | 0 2 2 0 | 0 1 2 1 0 | * 3 *
..xo ....&#x | 0 0 2 1 | 0 0 0 1 2 | * * 3
or
o...3o...    & | 2 * | 3 0 0 | 3 0
.o..3.o..    & | * 6 | 1 2 1 | 2 2
---------------+-----+-------+----
oo..3oo..&#x & | 1 1 | 6 * * | 2 0
.x.. ....    & | 0 2 | * 6 * | 1 1
.oo.3.oo.&#x   | 0 2 | * * 3 | 0 2
---------------+-----+-------+----
ox.. ....&#x & | 1 2 | 2 1 0 | 6 *
.xx. ....&#x   | 0 4 | 0 2 2 | * 3

xYx oox&#xt   → height(1,2) = 1/sqrt(3) = 0.577350
                height(2,3) = 1/sqrt(12) = 0.288675
                Y = sqrt[(11+4 sqrt(6))/3] = 2.632993
(pt || pseudo y-line || perp line)

o.. o..    | 2 * * | 1 1 2 0 0 0 | 2 2 0 0
.o. .o.    | * 2 * | 0 1 0 2 0 0 | 2 0 1 0
..o ..o    | * * 4 | 0 0 1 1 1 1 | 1 1 1 1
-----------+-------+-------------+--------
x.. ...    | 2 0 0 | 1 * * * * * | 0 2 0 0
oo. oo.&#x | 1 1 0 | * 2 * * * * | 2 0 0 0
o.o o.o&#x | 1 0 1 | * * 4 * * * | 1 1 0 0
.oo .oo&#x | 0 1 1 | * * * 4 * * | 1 0 1 0
..x ...    | 0 0 2 | * * * * 2 * | 0 1 0 1
... ..x    | 0 0 2 | * * * * * 2 | 0 0 1 1
-----------+-------+-------------+--------
ooo ooo&#x | 1 1 1 | 0 1 1 1 0 0 | 4 * * *
x.x ...&#x | 2 0 2 | 1 0 2 0 1 0 | * 2 * *
... .ox&#x | 0 1 2 | 0 0 0 2 0 1 | * * 2 *
..x ..x    | 0 0 4 | 0 0 0 0 2 2 | * * * 1

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