\[x.re \cdot y.re - x.im \cdot y.im\]
Test:
_multiplyComplex, real part
Bits:
128 bits
Bits error versus x.re
Bits error versus x.im
Bits error versus y.re
Bits error versus y.im
Time: 4.5 s
Input Error: 0.0
Output Error: 0.0
Log: ⚲
Profile: 🕒
\(x.re \cdot y.re - x.im \cdot y.im\)
  1. Started with
    \[x.re \cdot y.re - x.im \cdot y.im\]
    0.0
  2. Removed slow pow expressions

Original test:


(lambda ((x.re default) (x.im default) (y.re default) (y.im default))
  #:name "_multiplyComplex, real part"
  (- (* x.re y.re) (* x.im y.im)))