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# conformalBlockDegreeM04bar -- computes the degree of a conformal block bundle on $\bar{M}_{0,4}$

- Usage:
    `conformalBlockDegreeM04bar(V)`
- Inputs:
  - V, an instance of the type ConformalBlockVectorBundle,
- Outputs:
  - d, an integer,

## Description

This function implements the formula given in [Fakh] Corollary 3.5 for computing the degree of a conformal block vector bundle $V$ on $\bar{M}_{0,4}$.

The first line of the example below shows that the conformal block bundle $V(sl_3,1,(\omega_1,\omega_1,\omega_2,\omega_2))$ has degree 1 on $\bar{M}_{0,4} \cong \mathbb{P}^1$. The second line shows that this vector bundle is a line bundle. Hence, $V(sl_3,1,(\omega_1,\omega_1,\omega_2,\omega_2))$ is isomorphic to $\mathcal{O}(1)$.

    i1 : sl_3 = simpleLieAlgebra("A",2);

    i2 : V=conformalBlockVectorBundle(sl_3,1,{{1,0},{1,0},{0,1},{0,1}},0);

    i3 : conformalBlockDegreeM04bar(V)

    o3 = 1

    i4 : conformalBlockRank(V)

    o4 = 1

## Ways to use conformalBlockDegreeM04bar:

- `conformalBlockDegreeM04bar(ConformalBlockVectorBundle)`

## For the programmer

The object conformalBlockDegreeM04bar is a method function.

The source of this document is in /build/macaulay2-88fgJW/macaulay2-1.25.11+ds/M2/Macaulay2/packages/ConformalBlocks.m2:1518:0.