# Creation of Structures

## `AlgebraicClosure(K): Fld -> FldAC`

Create the algebraic closure **A** of the field $K$. Currently $K$ may be ${\mathbb{Q}}$, a finite field or a rational function field over a finite field or the rational field.

## `AlgebraicClosure() -> FldAC`

Create the algebraic closure **A** of the rational field ${\mathbb{Q}}$.

## `AssignNamePrefix(A, S): FldAC, MonStgElt`

(Procedure.) Given an algebraically closed field $A$ and a string $S$, reassign the string prefix of the names of $A$ to be $S$. By default, this prefix is `"r"`. When new variables are introduced by root taking, they are named by this prefix with the number appended (see `A.i` below).