
(FPCore (a b) :precision binary64 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b): return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b) return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b))) end
function tmp = code(a, b) tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b)); end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 8 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))
double code(double a, double b) {
return ((((double) M_PI) / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
public static double code(double a, double b) {
return ((Math.PI / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b));
}
def code(a, b): return ((math.pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b))
function code(a, b) return Float64(Float64(Float64(pi / 2.0) * Float64(1.0 / Float64(Float64(b * b) - Float64(a * a)))) * Float64(Float64(1.0 / a) - Float64(1.0 / b))) end
function tmp = code(a, b) tmp = ((pi / 2.0) * (1.0 / ((b * b) - (a * a)))) * ((1.0 / a) - (1.0 / b)); end
code[a_, b_] := N[(N[(N[(Pi / 2.0), $MachinePrecision] * N[(1.0 / N[(N[(b * b), $MachinePrecision] - N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(N[(1.0 / a), $MachinePrecision] - N[(1.0 / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\frac{\pi}{2} \cdot \frac{1}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1}{a} - \frac{1}{b}\right)
\end{array}
(FPCore (a b) :precision binary64 (/ (* (* 0.5 PI) (/ (+ (/ 1.0 a) (/ -1.0 b)) (+ a b))) (- b a)))
double code(double a, double b) {
return ((0.5 * ((double) M_PI)) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a);
}
public static double code(double a, double b) {
return ((0.5 * Math.PI) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a);
}
def code(a, b): return ((0.5 * math.pi) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a)
function code(a, b) return Float64(Float64(Float64(0.5 * pi) * Float64(Float64(Float64(1.0 / a) + Float64(-1.0 / b)) / Float64(a + b))) / Float64(b - a)) end
function tmp = code(a, b) tmp = ((0.5 * pi) * (((1.0 / a) + (-1.0 / b)) / (a + b))) / (b - a); end
code[a_, b_] := N[(N[(N[(0.5 * Pi), $MachinePrecision] * N[(N[(N[(1.0 / a), $MachinePrecision] + N[(-1.0 / b), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\left(0.5 \cdot \pi\right) \cdot \frac{\frac{1}{a} + \frac{-1}{b}}{a + b}}{b - a}
\end{array}
Initial program 73.3%
un-div-inv73.3%
difference-of-squares84.6%
associate-/r*85.0%
div-inv85.0%
metadata-eval85.0%
Applied egg-rr85.0%
associate-*l/99.7%
Applied egg-rr99.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
Final simplification99.7%
(FPCore (a b) :precision binary64 (* (* 0.5 PI) (/ (/ (+ (/ 1.0 a) (/ -1.0 b)) (+ a b)) (- b a))))
double code(double a, double b) {
return (0.5 * ((double) M_PI)) * ((((1.0 / a) + (-1.0 / b)) / (a + b)) / (b - a));
}
public static double code(double a, double b) {
return (0.5 * Math.PI) * ((((1.0 / a) + (-1.0 / b)) / (a + b)) / (b - a));
}
def code(a, b): return (0.5 * math.pi) * ((((1.0 / a) + (-1.0 / b)) / (a + b)) / (b - a))
function code(a, b) return Float64(Float64(0.5 * pi) * Float64(Float64(Float64(Float64(1.0 / a) + Float64(-1.0 / b)) / Float64(a + b)) / Float64(b - a))) end
function tmp = code(a, b) tmp = (0.5 * pi) * ((((1.0 / a) + (-1.0 / b)) / (a + b)) / (b - a)); end
code[a_, b_] := N[(N[(0.5 * Pi), $MachinePrecision] * N[(N[(N[(N[(1.0 / a), $MachinePrecision] + N[(-1.0 / b), $MachinePrecision]), $MachinePrecision] / N[(a + b), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(0.5 \cdot \pi\right) \cdot \frac{\frac{\frac{1}{a} + \frac{-1}{b}}{a + b}}{b - a}
\end{array}
Initial program 73.3%
un-div-inv73.3%
difference-of-squares84.6%
associate-/r*85.0%
div-inv85.0%
metadata-eval85.0%
Applied egg-rr85.0%
associate-*l/99.7%
Applied egg-rr99.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
associate-/l*99.6%
Applied egg-rr99.6%
Final simplification99.6%
(FPCore (a b) :precision binary64 (if (<= b 3e-200) (/ (/ (/ (* PI -0.5) a) b) (- b a)) (/ (/ (/ (* 0.5 PI) b) a) (- b a))))
double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (((((double) M_PI) * -0.5) / a) / b) / (b - a);
} else {
tmp = (((0.5 * ((double) M_PI)) / b) / a) / (b - a);
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (((Math.PI * -0.5) / a) / b) / (b - a);
} else {
tmp = (((0.5 * Math.PI) / b) / a) / (b - a);
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 3e-200: tmp = (((math.pi * -0.5) / a) / b) / (b - a) else: tmp = (((0.5 * math.pi) / b) / a) / (b - a) return tmp
function code(a, b) tmp = 0.0 if (b <= 3e-200) tmp = Float64(Float64(Float64(Float64(pi * -0.5) / a) / b) / Float64(b - a)); else tmp = Float64(Float64(Float64(Float64(0.5 * pi) / b) / a) / Float64(b - a)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 3e-200) tmp = (((pi * -0.5) / a) / b) / (b - a); else tmp = (((0.5 * pi) / b) / a) / (b - a); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 3e-200], N[(N[(N[(N[(Pi * -0.5), $MachinePrecision] / a), $MachinePrecision] / b), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(0.5 * Pi), $MachinePrecision] / b), $MachinePrecision] / a), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 3 \cdot 10^{-200}:\\
\;\;\;\;\frac{\frac{\frac{\pi \cdot -0.5}{a}}{b}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{\frac{0.5 \cdot \pi}{b}}{a}}{b - a}\\
\end{array}
\end{array}
if b < 2.99999999999999995e-200Initial program 72.4%
un-div-inv72.4%
difference-of-squares83.9%
associate-/r*84.7%
div-inv84.7%
metadata-eval84.7%
Applied egg-rr84.7%
associate-*l/99.6%
Applied egg-rr99.6%
Taylor expanded in b around 0 70.4%
associate-*r/70.4%
*-commutative70.4%
times-frac70.5%
Simplified70.5%
frac-times70.4%
associate-/r*70.5%
Applied egg-rr70.5%
if 2.99999999999999995e-200 < b Initial program 74.3%
un-div-inv74.3%
difference-of-squares85.4%
associate-/r*85.4%
div-inv85.4%
metadata-eval85.4%
Applied egg-rr85.4%
associate-*l/99.7%
Applied egg-rr99.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
Taylor expanded in a around 0 84.8%
associate-*r/84.8%
*-commutative84.8%
metadata-eval84.8%
distribute-rgt-neg-in84.8%
distribute-frac-neg84.8%
times-frac84.8%
associate-*l/84.8%
distribute-frac-neg84.8%
associate-*r/84.9%
distribute-frac-neg84.9%
distribute-rgt-neg-in84.9%
metadata-eval84.9%
*-commutative84.9%
Simplified84.9%
(FPCore (a b) :precision binary64 (if (<= b 3e-200) (/ (* PI (/ -0.5 (* a b))) (- b a)) (/ (/ (/ (* 0.5 PI) b) a) (- b a))))
double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (((double) M_PI) * (-0.5 / (a * b))) / (b - a);
} else {
tmp = (((0.5 * ((double) M_PI)) / b) / a) / (b - a);
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (Math.PI * (-0.5 / (a * b))) / (b - a);
} else {
tmp = (((0.5 * Math.PI) / b) / a) / (b - a);
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 3e-200: tmp = (math.pi * (-0.5 / (a * b))) / (b - a) else: tmp = (((0.5 * math.pi) / b) / a) / (b - a) return tmp
function code(a, b) tmp = 0.0 if (b <= 3e-200) tmp = Float64(Float64(pi * Float64(-0.5 / Float64(a * b))) / Float64(b - a)); else tmp = Float64(Float64(Float64(Float64(0.5 * pi) / b) / a) / Float64(b - a)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 3e-200) tmp = (pi * (-0.5 / (a * b))) / (b - a); else tmp = (((0.5 * pi) / b) / a) / (b - a); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 3e-200], N[(N[(Pi * N[(-0.5 / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(N[(N[(0.5 * Pi), $MachinePrecision] / b), $MachinePrecision] / a), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 3 \cdot 10^{-200}:\\
\;\;\;\;\frac{\pi \cdot \frac{-0.5}{a \cdot b}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{\frac{0.5 \cdot \pi}{b}}{a}}{b - a}\\
\end{array}
\end{array}
if b < 2.99999999999999995e-200Initial program 72.4%
un-div-inv72.4%
difference-of-squares83.9%
associate-/r*84.7%
div-inv84.7%
metadata-eval84.7%
Applied egg-rr84.7%
associate-*l/99.6%
Applied egg-rr99.6%
Taylor expanded in b around 0 70.4%
associate-*r/70.4%
*-commutative70.4%
Simplified70.4%
associate-/l*70.4%
Applied egg-rr70.4%
if 2.99999999999999995e-200 < b Initial program 74.3%
un-div-inv74.3%
difference-of-squares85.4%
associate-/r*85.4%
div-inv85.4%
metadata-eval85.4%
Applied egg-rr85.4%
associate-*l/99.7%
Applied egg-rr99.7%
associate-*l/99.6%
Applied egg-rr99.6%
associate-/l*99.7%
*-commutative99.7%
+-commutative99.7%
Simplified99.7%
Taylor expanded in a around 0 84.8%
associate-*r/84.8%
*-commutative84.8%
metadata-eval84.8%
distribute-rgt-neg-in84.8%
distribute-frac-neg84.8%
times-frac84.8%
associate-*l/84.8%
distribute-frac-neg84.8%
associate-*r/84.9%
distribute-frac-neg84.9%
distribute-rgt-neg-in84.9%
metadata-eval84.9%
*-commutative84.9%
Simplified84.9%
(FPCore (a b) :precision binary64 (if (<= b 3e-200) (/ (* PI (/ -0.5 (* a b))) (- b a)) (/ (/ (* 0.5 PI) (* a b)) (- b a))))
double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (((double) M_PI) * (-0.5 / (a * b))) / (b - a);
} else {
tmp = ((0.5 * ((double) M_PI)) / (a * b)) / (b - a);
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (Math.PI * (-0.5 / (a * b))) / (b - a);
} else {
tmp = ((0.5 * Math.PI) / (a * b)) / (b - a);
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 3e-200: tmp = (math.pi * (-0.5 / (a * b))) / (b - a) else: tmp = ((0.5 * math.pi) / (a * b)) / (b - a) return tmp
function code(a, b) tmp = 0.0 if (b <= 3e-200) tmp = Float64(Float64(pi * Float64(-0.5 / Float64(a * b))) / Float64(b - a)); else tmp = Float64(Float64(Float64(0.5 * pi) / Float64(a * b)) / Float64(b - a)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 3e-200) tmp = (pi * (-0.5 / (a * b))) / (b - a); else tmp = ((0.5 * pi) / (a * b)) / (b - a); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 3e-200], N[(N[(Pi * N[(-0.5 / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(N[(0.5 * Pi), $MachinePrecision] / N[(a * b), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 3 \cdot 10^{-200}:\\
\;\;\;\;\frac{\pi \cdot \frac{-0.5}{a \cdot b}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{0.5 \cdot \pi}{a \cdot b}}{b - a}\\
\end{array}
\end{array}
if b < 2.99999999999999995e-200Initial program 72.4%
un-div-inv72.4%
difference-of-squares83.9%
associate-/r*84.7%
div-inv84.7%
metadata-eval84.7%
Applied egg-rr84.7%
associate-*l/99.6%
Applied egg-rr99.6%
Taylor expanded in b around 0 70.4%
associate-*r/70.4%
*-commutative70.4%
Simplified70.4%
associate-/l*70.4%
Applied egg-rr70.4%
if 2.99999999999999995e-200 < b Initial program 74.3%
un-div-inv74.3%
difference-of-squares85.4%
associate-/r*85.4%
div-inv85.4%
metadata-eval85.4%
Applied egg-rr85.4%
associate-*l/99.7%
Applied egg-rr99.7%
Taylor expanded in b around inf 84.8%
associate-*r/84.8%
Simplified84.8%
(FPCore (a b) :precision binary64 (if (<= b 3e-200) (/ (* PI (/ -0.5 (* a b))) (- b a)) (/ (* (/ PI a) (/ 0.5 b)) (- b a))))
double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (((double) M_PI) * (-0.5 / (a * b))) / (b - a);
} else {
tmp = ((((double) M_PI) / a) * (0.5 / b)) / (b - a);
}
return tmp;
}
public static double code(double a, double b) {
double tmp;
if (b <= 3e-200) {
tmp = (Math.PI * (-0.5 / (a * b))) / (b - a);
} else {
tmp = ((Math.PI / a) * (0.5 / b)) / (b - a);
}
return tmp;
}
def code(a, b): tmp = 0 if b <= 3e-200: tmp = (math.pi * (-0.5 / (a * b))) / (b - a) else: tmp = ((math.pi / a) * (0.5 / b)) / (b - a) return tmp
function code(a, b) tmp = 0.0 if (b <= 3e-200) tmp = Float64(Float64(pi * Float64(-0.5 / Float64(a * b))) / Float64(b - a)); else tmp = Float64(Float64(Float64(pi / a) * Float64(0.5 / b)) / Float64(b - a)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if (b <= 3e-200) tmp = (pi * (-0.5 / (a * b))) / (b - a); else tmp = ((pi / a) * (0.5 / b)) / (b - a); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[b, 3e-200], N[(N[(Pi * N[(-0.5 / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision], N[(N[(N[(Pi / a), $MachinePrecision] * N[(0.5 / b), $MachinePrecision]), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \leq 3 \cdot 10^{-200}:\\
\;\;\;\;\frac{\pi \cdot \frac{-0.5}{a \cdot b}}{b - a}\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{\pi}{a} \cdot \frac{0.5}{b}}{b - a}\\
\end{array}
\end{array}
if b < 2.99999999999999995e-200Initial program 72.4%
un-div-inv72.4%
difference-of-squares83.9%
associate-/r*84.7%
div-inv84.7%
metadata-eval84.7%
Applied egg-rr84.7%
associate-*l/99.6%
Applied egg-rr99.6%
Taylor expanded in b around 0 70.4%
associate-*r/70.4%
*-commutative70.4%
Simplified70.4%
associate-/l*70.4%
Applied egg-rr70.4%
if 2.99999999999999995e-200 < b Initial program 74.3%
un-div-inv74.3%
difference-of-squares85.4%
associate-/r*85.4%
div-inv85.4%
metadata-eval85.4%
Applied egg-rr85.4%
associate-*l/99.7%
Applied egg-rr99.7%
Taylor expanded in b around inf 84.8%
associate-*r/84.8%
*-commutative84.8%
times-frac84.8%
Simplified84.8%
(FPCore (a b) :precision binary64 (* (* PI (/ 0.5 (+ a b))) (/ 1.0 (* a b))))
double code(double a, double b) {
return (((double) M_PI) * (0.5 / (a + b))) * (1.0 / (a * b));
}
public static double code(double a, double b) {
return (Math.PI * (0.5 / (a + b))) * (1.0 / (a * b));
}
def code(a, b): return (math.pi * (0.5 / (a + b))) * (1.0 / (a * b))
function code(a, b) return Float64(Float64(pi * Float64(0.5 / Float64(a + b))) * Float64(1.0 / Float64(a * b))) end
function tmp = code(a, b) tmp = (pi * (0.5 / (a + b))) * (1.0 / (a * b)); end
code[a_, b_] := N[(N[(Pi * N[(0.5 / N[(a + b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[(1.0 / N[(a * b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(\pi \cdot \frac{0.5}{a + b}\right) \cdot \frac{1}{a \cdot b}
\end{array}
Initial program 73.3%
un-div-inv73.3%
difference-of-squares84.6%
associate-/r*85.0%
div-inv85.0%
metadata-eval85.0%
Applied egg-rr85.0%
associate-*l/99.7%
Applied egg-rr99.7%
associate-/l*99.7%
associate-*r/99.6%
+-commutative99.6%
sub-neg99.6%
distribute-neg-frac99.6%
metadata-eval99.6%
Simplified99.6%
Taylor expanded in a around 0 99.6%
(FPCore (a b) :precision binary64 (* (/ PI a) (/ (/ -0.5 b) (- b a))))
double code(double a, double b) {
return (((double) M_PI) / a) * ((-0.5 / b) / (b - a));
}
public static double code(double a, double b) {
return (Math.PI / a) * ((-0.5 / b) / (b - a));
}
def code(a, b): return (math.pi / a) * ((-0.5 / b) / (b - a))
function code(a, b) return Float64(Float64(pi / a) * Float64(Float64(-0.5 / b) / Float64(b - a))) end
function tmp = code(a, b) tmp = (pi / a) * ((-0.5 / b) / (b - a)); end
code[a_, b_] := N[(N[(Pi / a), $MachinePrecision] * N[(N[(-0.5 / b), $MachinePrecision] / N[(b - a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\frac{\pi}{a} \cdot \frac{\frac{-0.5}{b}}{b - a}
\end{array}
Initial program 73.3%
un-div-inv73.3%
difference-of-squares84.6%
associate-/r*85.0%
div-inv85.0%
metadata-eval85.0%
Applied egg-rr85.0%
associate-*l/99.7%
Applied egg-rr99.7%
Taylor expanded in b around 0 66.1%
associate-*r/66.1%
*-commutative66.1%
times-frac66.1%
Simplified66.1%
*-un-lft-identity66.1%
associate-/l*66.2%
Applied egg-rr66.2%
*-lft-identity66.2%
Simplified66.2%
herbie shell --seed 2024165
(FPCore (a b)
:name "NMSE Section 6.1 mentioned, B"
:precision binary64
(* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))