Template:Frieze group notations

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Frieze groups
IUC Cox. Schön.* Orbifold Diagram§ Examples and
Conway nickname[1]
Description
p1 [∞]+
File:CDel node h2.pngFile:CDel infin.pngFile:CDel node h2.png
C
Z
∞∞ File:Frieze group 11.png File:Frieze example p1.png File:Frieze hop.png
hop
(T) Translations only:
This group is singly generated, by a translation by the smallest distance over which the pattern is periodic.
p11g [∞+,2+]
File:CDel node h2.pngFile:CDel infin.pngFile:CDel node h4.pngFile:CDel 2x.pngFile:CDel node h2.png
S
Z
∞× File:Frieze group 1g.png File:Frieze example p11g.png File:Frieze step.png
step
(TG) Glide-reflections and Translations:
This group is singly generated, by a glide reflection, with translations being obtained by combining two glide reflections.
p1m1 [∞]
File:CDel node.pngFile:CDel infin.pngFile:CDel node.png
C∞v
Dih
*∞∞ File:Frieze group m1.png File:Frieze example p1m1.png File:Frieze sidle.png
sidle
(TV) Vertical reflection lines and Translations:
The group is the same as the non-trivial group in the one-dimensional case; it is generated by a translation and a reflection in the vertical axis.
p2 [∞,2]+
File:CDel node h2.pngFile:CDel infin.pngFile:CDel node h2.pngFile:CDel 2x.pngFile:CDel node h2.png
D
Dih
22∞ File:Frieze group 12.png File:Frieze example p2.png File:Frieze spinning hop.png
spinning hop
(TR) Translations and 180° Rotations:
The group is generated by a translation and a 180° rotation.
p2mg [∞,2+]
File:CDel node.pngFile:CDel infin.pngFile:CDel node h2.pngFile:CDel 2x.pngFile:CDel node h2.png
D∞d
Dih
2*∞ File:Frieze group mg.png File:Frieze example p2mg.png File:Frieze spinning sidle.png
spinning sidle
(TRVG) Vertical reflection lines, Glide reflections, Translations and 180° Rotations:
The translations here arise from the glide reflections, so this group is generated by a glide reflection and either a rotation or a vertical reflection.
p11m [∞+,2]
File:CDel node h2.pngFile:CDel infin.pngFile:CDel node h2.pngFile:CDel 2.pngFile:CDel node.png
C∞h
Z×Dih1
∞* File:Frieze group 1m.png File:Frieze example p11m.png File:Frieze jump.png
jump
(THG) Translations, Horizontal reflections, Glide reflections:
This group is generated by a translation and the reflection in the horizontal axis. The glide reflection here arises as the composition of translation and horizontal reflection
p2mm [∞,2]
File:CDel node.pngFile:CDel infin.pngFile:CDel node.pngFile:CDel 2.pngFile:CDel node.png
D∞h
Dih×Dih1
*22∞ File:Frieze group mm.png File:Frieze example p2mm.png File:Frieze spinning jump.png
spinning jump
(TRHVG) Horizontal and Vertical reflection lines, Translations and 180° Rotations:
This group requires three generators, with one generating set consisting of a translation, the reflection in the horizontal axis and a reflection across a vertical axis.
*Schönflies's point group notation is extended here as infinite cases of the equivalent dihedral points symmetries
§The diagram shows one fundamental domain in yellow, with reflection lines in blue, glide reflection lines in dashed green, translation normals in red, and 2-fold gyration points as small green squares.
  1. ^ Frieze Patterns Mathematician John Conway created names that relate to footsteps for each of the frieze groups.