\[e^{a \cdot x} - 1\]
Test:
NMSE section 3.5
Bits:
128 bits
Bits error versus a
Bits error versus x
Time: 8.8 s
Input Error: 48.3
Output Error: 0.2
Log:
Profile: 🕒
\(\left(\left(x \cdot a\right) \cdot \left(x \cdot a\right)\right) \cdot \left(\frac{1}{2} + x \cdot \left(\frac{1}{6} \cdot a\right)\right) + x \cdot a\)
  1. Started with
    \[e^{a \cdot x} - 1\]
    48.3
  2. Applied taylor to get
    \[e^{a \cdot x} - 1 \leadsto \frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(\frac{1}{6} \cdot \left({a}^{3} \cdot {x}^{3}\right) + a \cdot x\right)\]
    21.4
  3. Taylor expanded around 0 to get
    \[\color{red}{\frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(\frac{1}{6} \cdot \left({a}^{3} \cdot {x}^{3}\right) + a \cdot x\right)} \leadsto \color{blue}{\frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(\frac{1}{6} \cdot \left({a}^{3} \cdot {x}^{3}\right) + a \cdot x\right)}\]
    21.4
  4. Applied simplify to get
    \[\color{red}{\frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(\frac{1}{6} \cdot \left({a}^{3} \cdot {x}^{3}\right) + a \cdot x\right)} \leadsto \color{blue}{\frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \left(\frac{1}{6} \cdot {a}^3\right) \cdot {x}^3\right)}\]
    21.4
  5. Using strategy rm
    21.4
  6. Applied add-cbrt-cube to get
    \[\frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \color{red}{\left(\frac{1}{6} \cdot {a}^3\right) \cdot {x}^3}\right) \leadsto \frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \color{blue}{\sqrt[3]{{\left(\left(\frac{1}{6} \cdot {a}^3\right) \cdot {x}^3\right)}^3}}\right)\]
    23.4
  7. Applied simplify to get
    \[\frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \sqrt[3]{\color{red}{{\left(\left(\frac{1}{6} \cdot {a}^3\right) \cdot {x}^3\right)}^3}}\right) \leadsto \frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \sqrt[3]{\color{blue}{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}}\right)\]
    9.0
  8. Applied taylor to get
    \[\frac{1}{2} \cdot {\left(x \cdot a\right)}^2 + \left(x \cdot a + \sqrt[3]{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}\right) \leadsto \frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(x \cdot a + \sqrt[3]{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}\right)\]
    17.9
  9. Taylor expanded around inf to get
    \[\frac{1}{2} \cdot \color{red}{\left({a}^2 \cdot {x}^2\right)} + \left(x \cdot a + \sqrt[3]{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}\right) \leadsto \frac{1}{2} \cdot \color{blue}{\left({a}^2 \cdot {x}^2\right)} + \left(x \cdot a + \sqrt[3]{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}\right)\]
    17.9
  10. Applied simplify to get
    \[\color{red}{\frac{1}{2} \cdot \left({a}^2 \cdot {x}^2\right) + \left(x \cdot a + \sqrt[3]{{\left(\frac{1}{6} \cdot {\left(a \cdot x\right)}^3\right)}^3}\right)} \leadsto \color{blue}{\left(\left(x \cdot a\right) \cdot \left(x \cdot a\right)\right) \cdot \left(\frac{1}{2} + x \cdot \left(\frac{1}{6} \cdot a\right)\right) + x \cdot a}\]
    0.2

Original test:


(lambda ((a default) (x default))
  #:name "NMSE section 3.5"
  (- (exp (* a x)) 1)
  #:target
  (if (< (fabs (* a x)) 1/10) (* (* a x) (+ 1 (+ (/ (* a x) 2) (/ (sqr (* a x)) 6)))) (- (exp (* a x)) 1)))