# CASA Function: toPlac

Converts an algebraic set given in implicit parametric or projected representation to an algebraic set represented by places.

### Calling Sequence:

• B := toPlac(A)
• B := toPlac(A,p)
• B := toPlac(A,p,var)

### Parameters:

A : {algset("impl"),algset("para"),algset("proj"),algset("plac")}
• algebraic set in implicit, parametric, place or projected representation
p : {casaCoeffType,list(casaCoeffType)}
• If p is a list, it specifies the center of the expansion. Otherwise such a point is computed by taking the point on the curve A that corresponts to the parameter p.
var : list(name)
• A variable to be used in the Puiseux expansion.

### Result:

B : algset("plac")
• The representation of the algebraic set given by places.

### Description:

• This function takes an algebraic set and converts it into an representation given by places. If the center point is omitted, it defaults to the origin (which must be on the curve).
• If no variable is given, the function chooses one.

### Examples:

> A := mkParaAlgSet([t,t^2,t^3],[t]);

> toPlac(A,[0,0,0],t);

> A := mkProjAlgSet([[u^2-v^3+v^2],[u+v,u-v,1/v]],[u,v]);

> toPlac(A,[1,-1,1]);