Pentagrammic Crossed Antiprism

Author

Eric W. Weisstein
September 11, 2023

This notebook downloaded from http://mathworld.wolfram.com/notebooks/Polyhedra/PentagrammicCrossedAntiprism.nb.

For more information, see Eric's MathWorld entry http://mathworld.wolfram.com/PentagrammicCrossedAntiprism.html.

©2023 Wolfram Research, Inc. except for portions noted otherwise

Polyhedron

PolyhedronData[stdname="PentagrammicCrossedAntiprism","Orientations"]

PolyhedronData[stdname]

Show[PolyhedronData[{stdname,#}],Boxed->False]&/@PolyhedronData[stdname,"Orientations"]

Polyhedron

Graphics3D[{FaceForm[Green,Red],PolyhedronData[stdname,"Polyhedron"]}]

Region

PolyhedronData[stdname,"Region"]

Solid and Dual

PolyhedronData[stdname,#]&/@{"Graphics3D","Dual","DualCompound"}

UniformPolyhedron

uniform=UniformPolyhedron[stdname="PentagrammicCrossedAntiprism"]

Bulatov

BulatovUniformName[UniformPolyhedronIndex[stdname,"Kaleido"]]

Graphics3D[#,Boxed->False]&/@{bulatov,polys}

Maeder

MaederUniformName[UniformPolyhedronIndex[stdname,"Maeder"]]

wythoff=MaederWythoffSymbol[UniformPolyhedronIndex[stdname,"Maeder"]]

With[{n=UniformPolyhedronIndex[stdname,"Maeder"]},Import["https://www.mathconsult.ch/static/unipoly/"<>If[n<10,"0",""]<>ToString[n]<>".html","Images"]][[1]]

maeder=MaederUniformPolyhedron[UniformPolyhedronIndex[stdname,"Maeder"]]

Graphics3D/@(polys=Polygon[maeder[[1]],#]&/@maeder[[2]])

PolyhedronFaceTally[maeder]

Graphics3D[#,Boxed->False]&/@{maeder,polys}

Properties

Initialization

<<MathWorld`Polyhedra`

p=PolyhedronData[pname="PentagrammicCrossedAntiprism","Polyhedron"]

Centroid

PolyhedronData[pname,"Centroid"]

Circumsphere

sphere=PolyhedronData[pname,"Circumsphere"]

Circumsphere[p]

(sphere=MyCircumsphere[p]//FullSimplify)//Timing

Graphics3D[{{Opacity[.3],Green,sphere},Blue,p},Boxed->False]

Classes

PolyhedronData[pname,"Classes"]

Compound

PolyhedronData[pname,"Compound"]

Concave

PolyhedronData[pname,"Concave"]

Convex

PolyhedronData[pname,"Convex"]

ConvexPolyhedronQ[p]

ConvexHull

hullname=PolyhedronData[pname,"ConvexHull","Name"]

PolyhedronData[pname,"ConvexHull","Scale"]

Graphics3D[convexhullp=PolyhedronData[pname,"ConvexHull","Polyhedron"]]

Graphics3D[convexhull=ConvexHullRegion[PolyhedronData[pname,"Vertices"]]]

PolyhedronEdgeLengths[convexhull]//RootReduce//Tally

v=PolyhedronCoordinates[convexhull]

Sort[(convexhull[[2]]/.i_Integer:>v[[i]])/.Thread[PolyhedronData[pname,"Vertices"]->Range[PolyhedronData[pname,"V"]]]]

Graphics3D[{FaceForm[Green,Red],convexhull,MapIndexed[Text[#2[[1]],#,Background->White]&,v]}]

{
Graphics3D[{p,MapIndexed[Text[#2[[1]],#,Background->White]&,v1=convexhull[[1]]]}],
Graphics3D[{hull=PolyhedronData[hullname,"Polyhedron"],MapIndexed[Text[#2[[1]],#,Background->White]&,v2=hull[[1]]]}]
}

((Norm[Most@v1[[1]]])/(Norm[Most@v2[[1]]]))//FullSimplify

((v1[[1,3]])/(v2[[2,3]]))//FullSimplify

{Graphics3D[{Red,Opacity[.5],p}],Graphics3D[{Blue,Opacity[.5],PolyhedronData[pname,"ConvexHull"][[1]]}]}

Show[%]

DehnInvariant

PolyhedronData[pname,"DehnInvariant"]

(dehn=DehnInvariant[p,Debug->True])//Timing

ToConwayBasis[dehn]

DihedralAngles

(dih1=PolyhedronData[pname,"DihedralAngles"])//Tally

(dih2=SimplifyNumericallyDistinct[DihedralAngles[p],"Simplification"->RootReduce]//FullSimplify)//Tally

dih1===dih2

Dual

pname

dname=PolyhedronData[pname,"Dual","Name"]

PolyhedronData[pname,"Dual","Scale"]

midrs={PolyhedronData[pname,"Midradius"],PolyhedronData[dname,"Midradius"]}

Divide@@midrs//FullSimplify

GraphicsRow[With[{
s={Yellow,PolyhedronData[pname,"Midsphere"]},
style=Directive[Black,Italic,FontFamily->"Times",14]
},
{
Graphics3D[{s,Green,Opacity[.5],PolyhedronData[pname,"Polyhedron"]},Boxed->False,PlotLabel->TextCell[Style[PolyhedronData[pname,"Name"],style],PageWidth->200,TextAlignment->Center]],
Graphics3D[{s,Red,Opacity[.5],PolyhedronData[pname,"Dual","Polyhedron"]},Boxed->False,PlotLabel->Style[PolyhedronData[dname,"Name"],style]],
Graphics3D[{
{Green,Opacity[.5],PolyhedronData[pname,"Polyhedron"]},
{Red,Opacity[.5],PolyhedronData[pname,"Dual","Polyhedron"]},
s
},Boxed->False,PlotLabel->Style["compound with midsphere",style]],
Graphics3D[{
PolyhedronData[pname,"Polyhedron"],
PolyhedronData[pname,"Dual","Polyhedron"]
},Boxed->False,PlotLabel->Style["compound",style]]
}],Alignment->Top,ImageSize->800]

EdgeCount

PolyhedronData[pname,"EdgeCount"]

EdgeLengths

PolyhedronData[pname,"EdgeLengths"]

Tally[lens=SimplifyNumericallyDistinct[PolyhedronEdgeLengths[p],"Simplification"->RootReduce]//FullSimplify]//Timing

SimplifyNumericallyDistinct[PolyhedronData[pname,"Lines"]/.Line[l_]:>EuclideanDistance@@l,"Simplification"->RootReduce]//FullSimplify//Tally//Timing

(distinctlens=Mean/@Split[Sort[lens],Abs[#1-#2]<1.*^-10&])//N//Quiet

v=p[[1]];

colors=With[{n=Length[distinctlens]},Table[Hue[i/n],{i,0,n-1}]]

Graphics3D[{Thick,Sequence@@Nearest[Thread[distinctlens->colors],EuclideanDistance@@v[[#]]],Line[v[[#]]]}&/@PolyhedronEdges[p],Boxed->False]//Quiet

FaceCount

PolyhedronData[pname,"FaceCount"]

FaceCountRules

PolyhedronData[pname,"FaceCountRules"]

PolyhedronFaceTally[p]

GeneralizedDiameter

PolyhedronData[pname,"GeneralizedDiameter"]

GeneralizedDiameter[p]//FullSimplify//Quiet

Hull

hullname=PolyhedronData[pname,"Hull","Name"]

PolyhedronData[pname,"Hull","Scale"]

{Graphics3D[{Opacity[.5],Red,p}],Graphics3D[{Opacity[.5],Blue,PolyhedronData[pname,"Hull"][[1]]}]}

Show[%]

InertiaTensor

PolyhedronData[pname,"InertiaTensor"]

Insphere

PolyhedronData[pname,"Insphere"]

Insphere[p]

MyInsphere[p//N]

sphere=MyInsphere[p]

MeanCylindricalRadius

PolyhedronData[pname,"MeanCylindricalRadius"]

MeanSquareCylindricalRadius

PolyhedronData[pname,"MeanSquareCylindricalRadius"]

MeanSphericalRadius

PolyhedronData[pname,"MeanSphericalRadius"]

MeanSquareSphericalRadius

PolyhedronData[pname,"MeanSquareSphericalRadius"]

Midsphere

sphere=PolyhedronData[pname,"Midsphere"]

Midsphere[N[p,200]]

RootApproximant[%[[2]]]

(sphere=Midsphere[p]//RootReduce)//Timing

(sphere=Midsphere[p,Method->"PointLineDistance"])//Timing

Graphics3D[{{Opacity[.5],Yellow,p},{Red,sphere}},Boxed->False]

Net

PolyhedronData[pname,"Net"]

NotationRules

PolyhedronData[pname,"NotationRules"]

Orientations

PolyhedronData[pname,"Orientations"]

PolyhedronData[pname,"DefaultOrientation"]

Show[PolyhedronData[{pname,#}],Boxed->False]&/@PolyhedronData[pname,"Orientations"]

Polygons

PolyhedronData[pname,"FaceCount"]

Graphics3D/@PolyhedronData[pname,"Polygons"]

Show[%]

Polyhedra

PolyhedronData[pname,"Polyhedra"]

Graphics3D[%]

PolyhedronData[pname,"PolyhedronIndices"]

Region

PolyhedronData[pname,"Region"]

RegionFunction

PolyhedronData[pname,"RegionFunction"]

SimplePolyhedron

PolyhedronData[pname,"Simple"]

SimplePolyhedronQ[p]

Skeleton

PolyhedronData[pname,"Skeleton"]

gn=PolyhedronData[pname,"Skeleton","Name"]

emb=GraphData[gn,"PolyhedralEmbeddings"]

GraphData[gn,"Graph",{"3D","All"}]

g=PolyhedronGraph[p]

SurfaceArea

PolyhedronData[pname,"SurfaceArea"]

SurfaceArea[p]

Total[Area/@PolyhedronData[pname,"Polygons"]]//ToAlgebraicRoot//FullSimplify

SurfaceArea[PolyhedronData[pname,"Region"]]

Uniform

PolyhedronData[pname,"Uniform"]

With[{rules=PolyhedronData[pname,"NotationRules"]},{
UniformPolyhedron[Lookup[rules,"WenningerIndex"]],
UniformPolyhedron[{"Coxeter",Lookup[rules,"CoxeterIndex"]}],
UniformPolyhedron[{"Kaleido",Lookup[rules,"KaleidoIndex"]}],
UniformPolyhedron[{"Uniform",Lookup[rules,"MaederIndex"]}],
UniformPolyhedron[{"Wenninger",Lookup[rules,"WenningerIndex"]}]
}]

SameQ@@%

VertexCount

PolyhedronData[pname,"VertexCount"]

VertexSubsetHulls

subsethulls=PolyhedronData[pname,"VertexSubsetHulls"]

v=PolyhedronData[pname,"Vertices"];

Rule[#,Length[#2]]&@@@subsethulls

Rule[#,Graphics3D[Function[f,ConvexHullRegion[v[[f]]]]/@#2]]&@@@subsethulls

subsethulls2=Flatten[Function[{pn,l},Rule[pn,#]&/@l]@@@subsethulls]

Rule[#,Graphics3D[{{Opacity[.3],{Green,p}},Blue,ConvexHullRegion[v[[#2]]]}]]&@@@subsethulls2

Convex hull

Graphics3D[convexhullreg=ConvexHullRegion[v=PolyhedronData[pname,"Vertices"]]]

v=PolyhedronCoordinates[convexhullreg]

Flatten[(convexhullreg[[2]]/.i_Integer:>v[[i]])/.Thread[PolyhedronData[pname,"Vertices"]->Range[PolyhedronData[pname,"V"]]]]//Union

%===Range@Length@v

PolyhedronData[pname,"ConvexHull","Name"]

Platonic

(h=VertexSubsetHulls[p,"Platonic","Skip"->{}])//Timing

Volume

PolyhedronData[pname,"Volume"]

Volume[p]

PolyhedronVolume[p]

Volume[PolyhedronData[pname,"Region"]]

WythoffSymbol

PolyhedronData[pname,"WythoffSymbol"]

Construction

c1=Append[#,h]&/@CirclePoints[{(Sqrt[(1/10) (5-(Sqrt[5]))]),0},5]

c2=Append[#,-h]&/@CirclePoints[{(Sqrt[(1/10) (5-(Sqrt[5]))]),Pi},5]

v=Join[c1,c2]

Graphics3D[{PointSize[.04],Point[v],MapIndexed[Text[#2[[1]],#,Background->White]&,v]}/.h->.25,Boxed->False]

FullSimplify[EuclideanDistance@@v[[{10,4}]],h>0]

Solve[%==1,h,PositiveReals]

v1=v/.h->(1/2) (Sqrt[(1/10) (5-(Sqrt[5]))]);

Graphics3D[{PointSize[.03],Point[{0,0,0}],FaceForm[Green,Red],p=Polyhedron[v1,{{1,3,5,2,4},Reverse@{7,9,6,8,10},{6,9,5},{4,8,2},{2,6,5},{1,3,7},{3,9,7},{8,4,10},{4,1,10},{9,3,5},{6,2,8},{7,10,1}}],MapIndexed[Text[#2[[1]],#,Background->White]&,v1]},Boxed->False]

PolyhedronEdgeLengths[p]//RootReduce//Quiet//Union

Midsphere[p//N]

PolyhedronDataString

file=OpenWrite["~/uniform.m"]

stdname="PentagrammicCrossedAntiprism";

wythoff=MaederWythoffSymbol[maederindex=UniformPolyhedronIndex[stdname,"Maeder"]]

WriteString[file,PolyhedronDataString[p,
"StandardName"->stdname,
"AlternateStandardNames"->{"U"<>ToString[maederindex],{"Uniform",maederindex}},
"Name"->StringTrim[StringReplace[stdname,RegularExpression["([A-Z])"]:>" "<>ToLowerCase["$1"]]],
"Information"->stdname,
"WythoffSymbol"->wythoff/.{
w0[p_,q_,r_]:>{{},{p,q,r}},
w1[p_,q_,r_]:>{{p},{q,r}},
w2[p_,q_,r_]:>{{p,q},{r}},
w3[p_,q_,r_]:>{{p,q,r}},
w4[p_,q_,r_,s_]:>{{},{p,q,r,s}}
},
"Classes"->{"Canonical","Equilateral","Uniform"},
"NotationRules"->{"KaleidoIndex"->5,"MaederIndex"->80}
]]

Close[file]