Average Error: 5.4 → 4.3
Time: 25.3s
Precision: 64
Internal Precision: 128
\[\left(\left(\left(\left(\left(\left(x \cdot 18.0\right) \cdot y\right) \cdot z\right) \cdot t - \left(a \cdot 4.0\right) \cdot t\right) + b \cdot c\right) - \left(x \cdot 4.0\right) \cdot i\right) - \left(j \cdot 27.0\right) \cdot k\]
\[\begin{array}{l} \mathbf{if}\;t \le -2.757625985983166 \cdot 10^{-115}:\\ \;\;\;\;\left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right) + t \cdot \left(\left(\left(x \cdot z\right) \cdot y\right) \cdot 18.0 - a \cdot 4.0\right)\\ \mathbf{elif}\;t \le 1.5812996223887337 \cdot 10^{-176}:\\ \;\;\;\;\left(a \cdot 4.0\right) \cdot \left(-t\right) + \left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right) + t \cdot \left(\left(\left(x \cdot z\right) \cdot y\right) \cdot 18.0 - a \cdot 4.0\right)\\ \end{array}\]

Error

Bits error versus x

Bits error versus y

Bits error versus z

Bits error versus t

Bits error versus a

Bits error versus b

Bits error versus c

Bits error versus i

Bits error versus j

Bits error versus k

Derivation

  1. Split input into 2 regimes
  2. if t < -2.757625985983166e-115 or 1.5812996223887337e-176 < t

    1. Initial program 3.1

      \[\left(\left(\left(\left(\left(\left(x \cdot 18.0\right) \cdot y\right) \cdot z\right) \cdot t - \left(a \cdot 4.0\right) \cdot t\right) + b \cdot c\right) - \left(x \cdot 4.0\right) \cdot i\right) - \left(j \cdot 27.0\right) \cdot k\]
    2. Simplified3.2

      \[\leadsto \color{blue}{\left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \left(y \cdot \left(\left(x \cdot 18.0\right) \cdot z\right) - a \cdot 4.0\right) \cdot t}\]
    3. Taylor expanded around -inf 4.1

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \color{blue}{\left(18.0 \cdot \left(t \cdot \left(x \cdot \left(z \cdot y\right)\right)\right) - 4.0 \cdot \left(t \cdot a\right)\right)}\]
    4. Simplified3.2

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \color{blue}{t \cdot \left(\left(x \cdot z\right) \cdot \left(y \cdot 18.0\right) - 4.0 \cdot a\right)}\]
    5. Using strategy rm
    6. Applied associate-*l*3.2

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \color{blue}{x \cdot \left(4.0 \cdot i\right)}\right)\right) + t \cdot \left(\left(x \cdot z\right) \cdot \left(y \cdot 18.0\right) - 4.0 \cdot a\right)\]
    7. Using strategy rm
    8. Applied associate-*r*3.2

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + x \cdot \left(4.0 \cdot i\right)\right)\right) + t \cdot \left(\color{blue}{\left(\left(x \cdot z\right) \cdot y\right) \cdot 18.0} - 4.0 \cdot a\right)\]

    if -2.757625985983166e-115 < t < 1.5812996223887337e-176

    1. Initial program 9.6

      \[\left(\left(\left(\left(\left(\left(x \cdot 18.0\right) \cdot y\right) \cdot z\right) \cdot t - \left(a \cdot 4.0\right) \cdot t\right) + b \cdot c\right) - \left(x \cdot 4.0\right) \cdot i\right) - \left(j \cdot 27.0\right) \cdot k\]
    2. Simplified9.0

      \[\leadsto \color{blue}{\left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \left(y \cdot \left(\left(x \cdot 18.0\right) \cdot z\right) - a \cdot 4.0\right) \cdot t}\]
    3. Taylor expanded around -inf 10.7

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \color{blue}{\left(18.0 \cdot \left(t \cdot \left(x \cdot \left(z \cdot y\right)\right)\right) - 4.0 \cdot \left(t \cdot a\right)\right)}\]
    4. Simplified9.1

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \left(x \cdot 4.0\right) \cdot i\right)\right) + \color{blue}{t \cdot \left(\left(x \cdot z\right) \cdot \left(y \cdot 18.0\right) - 4.0 \cdot a\right)}\]
    5. Using strategy rm
    6. Applied associate-*l*9.2

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + \color{blue}{x \cdot \left(4.0 \cdot i\right)}\right)\right) + t \cdot \left(\left(x \cdot z\right) \cdot \left(y \cdot 18.0\right) - 4.0 \cdot a\right)\]
    7. Taylor expanded around 0 6.6

      \[\leadsto \left(c \cdot b - \left(\left(27.0 \cdot j\right) \cdot k + x \cdot \left(4.0 \cdot i\right)\right)\right) + t \cdot \left(\color{blue}{0} - 4.0 \cdot a\right)\]
  3. Recombined 2 regimes into one program.
  4. Final simplification4.3

    \[\leadsto \begin{array}{l} \mathbf{if}\;t \le -2.757625985983166 \cdot 10^{-115}:\\ \;\;\;\;\left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right) + t \cdot \left(\left(\left(x \cdot z\right) \cdot y\right) \cdot 18.0 - a \cdot 4.0\right)\\ \mathbf{elif}\;t \le 1.5812996223887337 \cdot 10^{-176}:\\ \;\;\;\;\left(a \cdot 4.0\right) \cdot \left(-t\right) + \left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right)\\ \mathbf{else}:\\ \;\;\;\;\left(c \cdot b - \left(\left(i \cdot 4.0\right) \cdot x + k \cdot \left(j \cdot 27.0\right)\right)\right) + t \cdot \left(\left(\left(x \cdot z\right) \cdot y\right) \cdot 18.0 - a \cdot 4.0\right)\\ \end{array}\]

Reproduce

herbie shell --seed 2019093 
(FPCore (x y z t a b c i j k)
  :name "Diagrams.Solve.Polynomial:cubForm  from diagrams-solve-0.1"
  (- (- (+ (- (* (* (* (* x 18.0) y) z) t) (* (* a 4.0) t)) (* b c)) (* (* x 4.0) i)) (* (* j 27.0) k)))