pRing -- Constructs the ring of probability coordinates

Synopsis

Usage:

S = pRing(T,M)

S = pRing(n,M)
Inputs:
- T, an instance of the type LeafTree, A tree
- n, an integer, The number of leaves
- M, an instance of the type Model, The model (CNFmodel, JCmodel, etc)
Outputs:
- S, a ring, The ring of probability coordinates

Description

The probability coordinates for a phylogenetic tree model have one coordinate for each possible outcome of the model. A possible outcome is any labeling of the leaves of the tree by elements of the group $G$ of the model. Thus the number of coordinates is $|G|^n$ where $n$ is the number of leaves.

The variables use symbol p.

i1 : pRing(4,CFNmodel)

o1 = QQ[p       ..p       ]
         0,0,0,0   1,1,1,1

o1 : PolynomialRing

i2 : pRing(3,JCmodel)

o2 = QQ[p     ..p     ]
         0,0,0   3,3,3

o2 : PolynomialRing

Ways to use `pRing` :

"pRing(LeafTree,Model)"
"pRing(ZZ,Model)"

For the programmer

The object pRing is a method function.

pRing -- Constructs the ring of probability coordinates

Synopsis

Description

See also

Ways to use pRing :

For the programmer

Ways to use `pRing` :