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# getScalar -- returns the non-zero scalar of an unstable Grothendieck-Witt class

- Usage:
    `getScalar(beta)`
- Inputs:
  - beta, an Unstable Grothendieck-Witt Class, an unstable Grothendieck-Witt class
- Outputs:
  - a ring element, the non-zero scalar of the unstable Grothendieck-Witt class

## Description

Given an UnstableGrothendieckWittClass object beta, this method returns the non-zero scalar of the unstable Grothendieck-Witt class. This scalar is an element of the base field or finite étale algebra of the unstable Grothendieck-Witt class.

    i1 : M = matrix(QQ, {{0,1},{1,0}})

    o1 = | 0 1 |
         | 1 0 |

                  2       2
    o1 : Matrix QQ  <-- QQ

    i2 : getScalar makeGWuClass(M, -4)

    o2 = -4

    o2 : QQ

## See also

- UnstableGrothendieckWittClass -- a new type intended to capture an element of the unstable Grothendieck-Witt group of a field or finite étale algebras over a field
- getAlgebra -- returns the algebra over which a stable or unstable Grothendieck-Witt class is defined
- getBaseField -- returns the base field of a stable or unstable Grothendieck-Witt class
- getMatrix -- returns the Gram matrix of a stable or unstable Grothendieck-Witt class
- makeGWuClass -- constructor for unstable Grothendieck-Witt classes

## Ways to use getScalar:

- `getScalar(UnstableGrothendieckWittClass)`

## For the programmer

The object getScalar is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/A1BrouwerDegrees/Documentation/UnstableGrothendieckWittClassesDoc.m2:250:0.