
(FPCore (a b) :precision binary64 (- (* a a) (* b b)))
double code(double a, double b) {
return (a * a) - (b * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a * a) - (b * b)
end function
public static double code(double a, double b) {
return (a * a) - (b * b);
}
def code(a, b): return (a * a) - (b * b)
function code(a, b) return Float64(Float64(a * a) - Float64(b * b)) end
function tmp = code(a, b) tmp = (a * a) - (b * b); end
code[a_, b_] := N[(N[(a * a), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot a - b \cdot b
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 4 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (a b) :precision binary64 (- (* a a) (* b b)))
double code(double a, double b) {
return (a * a) - (b * b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a * a) - (b * b)
end function
public static double code(double a, double b) {
return (a * a) - (b * b);
}
def code(a, b): return (a * a) - (b * b)
function code(a, b) return Float64(Float64(a * a) - Float64(b * b)) end
function tmp = code(a, b) tmp = (a * a) - (b * b); end
code[a_, b_] := N[(N[(a * a), $MachinePrecision] - N[(b * b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
a \cdot a - b \cdot b
\end{array}
(FPCore (a b) :precision binary64 (* (- a b) (+ a b)))
double code(double a, double b) {
return (a - b) * (a + b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a - b) * (a + b)
end function
public static double code(double a, double b) {
return (a - b) * (a + b);
}
def code(a, b): return (a - b) * (a + b)
function code(a, b) return Float64(Float64(a - b) * Float64(a + b)) end
function tmp = code(a, b) tmp = (a - b) * (a + b); end
code[a_, b_] := N[(N[(a - b), $MachinePrecision] * N[(a + b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(a - b\right) \cdot \left(a + b\right)
\end{array}
Initial program 95.7%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt55.4%
sqrt-unprod76.8%
sqr-neg76.8%
sqrt-prod22.5%
add-sqr-sqrt49.6%
Applied egg-rr49.6%
add-sqr-sqrt22.5%
sqrt-prod76.8%
add-sqr-sqrt21.8%
add-sqr-sqrt21.8%
sqr-neg21.8%
swap-sqr21.8%
sqrt-unprod0.0%
add-sqr-sqrt44.4%
distribute-rgt-neg-out44.4%
add-sqr-sqrt100.0%
sub-neg100.0%
Applied egg-rr100.0%
(FPCore (a b) :precision binary64 (if (<= (* b b) 2e+57) (* a a) (* b (- a b))))
double code(double a, double b) {
double tmp;
if ((b * b) <= 2e+57) {
tmp = a * a;
} else {
tmp = b * (a - b);
}
return tmp;
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8) :: tmp
if ((b * b) <= 2d+57) then
tmp = a * a
else
tmp = b * (a - b)
end if
code = tmp
end function
public static double code(double a, double b) {
double tmp;
if ((b * b) <= 2e+57) {
tmp = a * a;
} else {
tmp = b * (a - b);
}
return tmp;
}
def code(a, b): tmp = 0 if (b * b) <= 2e+57: tmp = a * a else: tmp = b * (a - b) return tmp
function code(a, b) tmp = 0.0 if (Float64(b * b) <= 2e+57) tmp = Float64(a * a); else tmp = Float64(b * Float64(a - b)); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if ((b * b) <= 2e+57) tmp = a * a; else tmp = b * (a - b); end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[N[(b * b), $MachinePrecision], 2e+57], N[(a * a), $MachinePrecision], N[(b * N[(a - b), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;b \cdot b \leq 2 \cdot 10^{+57}:\\
\;\;\;\;a \cdot a\\
\mathbf{else}:\\
\;\;\;\;b \cdot \left(a - b\right)\\
\end{array}
\end{array}
if (*.f64 b b) < 2.0000000000000001e57Initial program 100.0%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt57.3%
sqrt-unprod90.6%
sqr-neg90.6%
sqrt-prod33.3%
add-sqr-sqrt78.2%
Applied egg-rr78.2%
Taylor expanded in a around inf 78.6%
Taylor expanded in a around inf 78.9%
if 2.0000000000000001e57 < (*.f64 b b) Initial program 90.8%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt53.2%
sqrt-unprod61.2%
sqr-neg61.2%
sqrt-prod10.4%
add-sqr-sqrt17.2%
Applied egg-rr17.2%
add-sqr-sqrt10.4%
sqrt-prod61.2%
add-sqr-sqrt8.7%
add-sqr-sqrt8.7%
sqr-neg8.7%
swap-sqr8.7%
sqrt-unprod0.0%
add-sqr-sqrt46.5%
distribute-rgt-neg-out46.5%
add-sqr-sqrt100.0%
sub-neg100.0%
Applied egg-rr100.0%
Taylor expanded in a around 0 86.6%
Final simplification82.5%
(FPCore (a b) :precision binary64 (if (<= (* a a) 4e+192) (* b (- b)) (* a a)))
double code(double a, double b) {
double tmp;
if ((a * a) <= 4e+192) {
tmp = b * -b;
} else {
tmp = a * a;
}
return tmp;
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
real(8) :: tmp
if ((a * a) <= 4d+192) then
tmp = b * -b
else
tmp = a * a
end if
code = tmp
end function
public static double code(double a, double b) {
double tmp;
if ((a * a) <= 4e+192) {
tmp = b * -b;
} else {
tmp = a * a;
}
return tmp;
}
def code(a, b): tmp = 0 if (a * a) <= 4e+192: tmp = b * -b else: tmp = a * a return tmp
function code(a, b) tmp = 0.0 if (Float64(a * a) <= 4e+192) tmp = Float64(b * Float64(-b)); else tmp = Float64(a * a); end return tmp end
function tmp_2 = code(a, b) tmp = 0.0; if ((a * a) <= 4e+192) tmp = b * -b; else tmp = a * a; end tmp_2 = tmp; end
code[a_, b_] := If[LessEqual[N[(a * a), $MachinePrecision], 4e+192], N[(b * (-b)), $MachinePrecision], N[(a * a), $MachinePrecision]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;a \cdot a \leq 4 \cdot 10^{+192}:\\
\;\;\;\;b \cdot \left(-b\right)\\
\mathbf{else}:\\
\;\;\;\;a \cdot a\\
\end{array}
\end{array}
if (*.f64 a a) < 4.00000000000000016e192Initial program 100.0%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt56.8%
sqrt-unprod69.6%
sqr-neg69.6%
sqrt-prod12.6%
add-sqr-sqrt29.0%
Applied egg-rr29.0%
add-sqr-sqrt12.6%
sqrt-prod69.6%
add-sqr-sqrt12.6%
add-sqr-sqrt12.6%
sqr-neg12.6%
swap-sqr12.6%
sqrt-unprod0.0%
add-sqr-sqrt42.9%
distribute-rgt-neg-out42.9%
add-sqr-sqrt100.0%
sub-neg100.0%
Applied egg-rr100.0%
Taylor expanded in a around 0 75.0%
Taylor expanded in a around 0 75.2%
neg-mul-175.2%
Simplified75.2%
if 4.00000000000000016e192 < (*.f64 a a) Initial program 86.9%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt52.4%
sqrt-unprod91.7%
sqr-neg91.7%
sqrt-prod42.9%
add-sqr-sqrt91.7%
Applied egg-rr91.7%
Taylor expanded in a around inf 95.4%
Taylor expanded in a around inf 91.7%
Final simplification80.6%
(FPCore (a b) :precision binary64 (* a a))
double code(double a, double b) {
return a * a;
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = a * a
end function
public static double code(double a, double b) {
return a * a;
}
def code(a, b): return a * a
function code(a, b) return Float64(a * a) end
function tmp = code(a, b) tmp = a * a; end
code[a_, b_] := N[(a * a), $MachinePrecision]
\begin{array}{l}
\\
a \cdot a
\end{array}
Initial program 95.7%
difference-of-squares100.0%
sub-neg100.0%
add-sqr-sqrt55.4%
sqrt-unprod76.8%
sqr-neg76.8%
sqrt-prod22.5%
add-sqr-sqrt49.6%
Applied egg-rr49.6%
Taylor expanded in a around inf 52.3%
Taylor expanded in a around inf 50.4%
(FPCore (a b) :precision binary64 (* (+ a b) (- a b)))
double code(double a, double b) {
return (a + b) * (a - b);
}
real(8) function code(a, b)
real(8), intent (in) :: a
real(8), intent (in) :: b
code = (a + b) * (a - b)
end function
public static double code(double a, double b) {
return (a + b) * (a - b);
}
def code(a, b): return (a + b) * (a - b)
function code(a, b) return Float64(Float64(a + b) * Float64(a - b)) end
function tmp = code(a, b) tmp = (a + b) * (a - b); end
code[a_, b_] := N[(N[(a + b), $MachinePrecision] * N[(a - b), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
\\
\left(a + b\right) \cdot \left(a - b\right)
\end{array}
herbie shell --seed 2024139
(FPCore (a b)
:name "Difference of squares"
:precision binary64
:alt
(! :herbie-platform default (* (+ a b) (- a b)))
(- (* a a) (* b b)))