Movatterモバイル変換

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Acronym	recta
Name	rectangular alterprism, rectangular trapezoprism
Circumradius	sqrt[c²+(a+b)²/2]/2
Snub derivation / VRML	⭳ case: (a,b,c) = (x,w,q)
Lace city in approx. ASCII-art	a a b b
Coordinates	(a/2, b/2; sqrt[c²-(b-a)²/2]/2) & all changes of sign in first 2 coords (b/2, a/2; -sqrt[c²-(b-a)²/2]/2) & all changes of sign in first 2 coords
Dihedral angles (at margins)	at a-edge (short side of rectangle): arccos(1/sqrt[4c²/(b-a)²-1]) at b-edge (long side of rectangle): arccos(-1/sqrt[4c²/(b-a)²-1]) at c-edge (lacings): arccos(1/[4c²/(b-a)²-1])
Face vector	8, 12, 6
Confer	regular variant: cube

The variant with (a,b,c) = (x,w,q) occurs as the mere base-edge alternated facetings2s4x obtained from theop.

Incidence matrix according toDynkin symbol

ab ba&#c   → height = sqrt[c²-(b-a)²/2]             a < b             c > (b-a)/sqrt(2)o. o.    | 4 * | 1 1 1 0 0 | 1 1 1 0.o .o    | * 4 | 0 0 1 1 1 | 0 1 1 1---------+-----+-----------+--------a. ..    | 2 0 | 2 * * * * | 1 1 0 0.. b.    | 2 0 | * 2 * * * | 1 0 1 0oo oo&#c | 1 1 | * * 4 * * | 0 1 1 0.b ..    | 0 2 | * * * 2 * | 0 1 0 1.. .a    | 0 2 | * * * * 2 | 0 0 1 1---------+-----+-----------+--------a. b.    | 4 0 | 2 2 0 0 0 |1 * * *  rectangleab ..&#c | 2 2 | 1 0 2 1 0 | * 2 * *  trapezium.. ba&#c | 2 2 | 0 1 2 0 1 | * * 2 *  trapezium.b .a    | 0 4 | 0 0 0 2 2 | * * *1  rectangle

oro. o.    & | 8 | 1 1 1 | 1 2-----------+---+-------+----a. ..    & | 2 | 4 * * | 1 1.. b.    & | 2 | * 4 * | 1 1oo oo&#c   | 2 | * * 4 | 0 2-----------+---+-------+----a. b.    & | 4 | 2 2 0 |2 *  rectangleab ..&#c   | 4 | 1 1 2 | * 4  trapezium

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