Average Error: 3.8 → 3.2
Time: 33.9s
Precision: 64
Internal Precision: 576
\[\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sin th\]
\[\begin{array}{l} \mathbf{if}\;\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \le 0.9999999993477511:\\ \;\;\;\;\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + \left(\sqrt[3]{{\left(\sin ky\right)}^{2}} \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}\right) \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}}} \cdot \sin th\\ \mathbf{else}:\\ \;\;\;\;\sin th \cdot \left(1 - {kx}^{2} \cdot \frac{1}{6}\right)\\ \end{array}\]

Error

Bits error versus kx

Bits error versus ky

Bits error versus th

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if (/ (sin ky) (sqrt (+ (pow (sin kx) 2) (pow (sin ky) 2)))) < 0.9999999993477511

    1. Initial program 2.5

      \[\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sin th\]
    2. Using strategy rm
    3. Applied add-cube-cbrt2.8

      \[\leadsto \frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + \color{blue}{\left(\sqrt[3]{{\left(\sin ky\right)}^{2}} \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}\right) \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}}}} \cdot \sin th\]

    if 0.9999999993477511 < (/ (sin ky) (sqrt (+ (pow (sin kx) 2) (pow (sin ky) 2))))

    1. Initial program 9.0

      \[\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sin th\]
    2. Using strategy rm
    3. Applied add-sqr-sqrt9.0

      \[\leadsto \frac{\sin ky}{\sqrt{\color{blue}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}} \cdot \sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}}}} \cdot \sin th\]
    4. Applied sqrt-prod9.5

      \[\leadsto \frac{\sin ky}{\color{blue}{\sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}}}} \cdot \sin th\]
    5. Applied *-un-lft-identity9.5

      \[\leadsto \frac{\color{blue}{1 \cdot \sin ky}}{\sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \cdot \sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}}} \cdot \sin th\]
    6. Applied times-frac9.5

      \[\leadsto \color{blue}{\left(\frac{1}{\sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}}} \cdot \frac{\sin ky}{\sqrt{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}}}\right)} \cdot \sin th\]
    7. Taylor expanded around 0 4.6

      \[\leadsto \color{blue}{\left(1 - \frac{1}{6} \cdot {kx}^{2}\right)} \cdot \sin th\]
  3. Recombined 2 regimes into one program.
  4. Final simplification3.2

    \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + {\left(\sin ky\right)}^{2}}} \le 0.9999999993477511:\\ \;\;\;\;\frac{\sin ky}{\sqrt{{\left(\sin kx\right)}^{2} + \left(\sqrt[3]{{\left(\sin ky\right)}^{2}} \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}\right) \cdot \sqrt[3]{{\left(\sin ky\right)}^{2}}}} \cdot \sin th\\ \mathbf{else}:\\ \;\;\;\;\sin th \cdot \left(1 - {kx}^{2} \cdot \frac{1}{6}\right)\\ \end{array}\]

Runtime

Time bar (total: 33.9s)Debug logProfile

herbie shell --seed 2018255 
(FPCore (kx ky th)
  :name "Toniolo and Linder, Equation (3b), real"
  (* (/ (sin ky) (sqrt (+ (pow (sin kx) 2) (pow (sin ky) 2)))) (sin th)))