adjoint.js
function adjoint(out, a) {
  // Caching this value is nessecary if out == a
  var a0 =  a[0]
  out[0] =  a[3]
  out[1] = -a[1]
  out[2] = -a[2]
  out[3] =  a0

  return out
}
function adjoint(out, a) {
  // Caching this value is nessecary if out == a
  var a0 =  a[0]
  out[0] =  a[3]
  out[1] = -a[1]
  out[2] = -a[2]
  out[3] =  a0

  return out
}
function adjoint ( out , a ) { // Caching this value is nessecary if out == a var a0 = a [ 0 ] out [ 0 ] = a [ 3 ] out [ 1 ] = - a [ 1 ] out [ 2 ] = - a [ 2 ] out [ 3 ] = a0 return out }
Calculates the adjugate of a mat2

@alias mat2.adjoint
@param {mat2} out the receiving matrix
@param {mat2} a the source matrix
@returns {mat2} out
Calculates the adjugate of a mat2