Acronym tatriddip Name truncated triangular duoprism Circumradius sqrt[(2y2+5x+5)/3] Confer extremal cases: triddip   retdip Externallinks

Truncation wrt. a non-regular polytope is meant to any instance of truncations on all vertices. For pre-images with different edge types however the ratio correlation of the remaining bits of those becomes arbitrary. Therefore triddip cannot be truncated (within this stronger sense). Nonetheless the Conway operator of ambification (chosing the edge centers generally) clearly is applicable. And thus an expansion of that ambification could replace the usual expansion of the rectification here. This would result in 3 different edge sizes in the outcome polyhedron. That one here is scaled such so that the shorter specified one becomes unity. Then the larger specified edge will have size q=sqrt(2). The third one would be the arbitrary expansion size y (corresponding to the arbitrary truncation depth). In fact, for y=0 this results again in the retdip, while y → ∞ results again in the pre-image triddip (rescaled back down accordingly).

Incidence matrix according to Dynkin symbol

```xo3yb by3ox&#zq   → height = 0
y > 0 (arbitrary expansion size), b = y+2 (pseudo)
b = y+2 (pseudo)
(q-laced tegum sum of 2 alternate (x,y,b)-thiddips)

o.3o. o.3o.     & | 36 |  1  1  2 | 1  3 2 | 3 1
------------------+----+----------+--------+----
x. .. .. ..     & |  2 | 18  *  * | 1  2 0 | 2 1
.. y. .. ..     & |  2 |  * 18  * | 1  0 2 | 3 0
oo3oo oo3oo&#q    |  2 |  *  * 36 | 0  2 1 | 2 1
------------------+----+----------+--------+----
x.3y. .. ..     & |  6 |  3  3  0 | 6  * * | 2 0
xo .. .. ..&#q  & |  3 |  1  0  2 | * 36 * | 1 1
.. yb by ..&#zq   |  8 |  0  4  4 | *  * 9 | 2 0
------------------+----+----------+--------+----
xo3yb by ..&#zq & | 18 |  6  9 12 | 2  6 3 | 6 *  truncated trip
xo .. .. ox&#q    |  4 |  2  0  4 | 0  4 0 | * 9  disphenoid
```