ndarray_cg 0.4.0

High-performance computer graphics mathematics library based on ndarray with vectors, matrices, and transformations
Documentation 
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use crate::*;

impl< E, Descriptor > Mat2< E, Descriptor > 
where 
E : MatEl + nd::NdFloat,
Descriptor : mat::Descriptor,
Self : RawSliceMut< Scalar = E > +
       ScalarMut< Scalar = E, Index = Ix2 > + 
       ConstLayout< Index = Ix2 > + 
       IndexingMut< Scalar = E, Index = Ix2 >
{
  /// Computes the determinant of the matrix
  pub fn determinant( &self ) -> E
  {
    let a = *self.scalar_ref( Ix2( 0, 0 ) );
    let b = *self.scalar_ref( Ix2( 0, 1 ) );
    let c = *self.scalar_ref( Ix2( 1, 0 ) );
    let d = *self.scalar_ref( Ix2( 1, 1 ) );

    a * d - b * c
  }    

  /// Computes the inverse of the matrix.
  /// If the determinant is zero - return `None`
  pub fn inverse( &self ) -> Option< Self >
  {
    let det = self.determinant();

    if det == E::zero() { return None; }

    let a = *self.scalar_ref( Ix2( 0, 0 ) );
    let b = *self.scalar_ref( Ix2( 0, 1 ) );
    let c = *self.scalar_ref( Ix2( 1, 0 ) );
    let d = *self.scalar_ref( Ix2( 1, 1 ) );

    let inverse = Self::from_column_major
    (
      [ d, -c, -b, a ]
    );

    Some( inverse / det )
  }
}