
(FPCore (x y z t) :precision binary64 (* (- (* x y) (* z y)) t))
double code(double x, double y, double z, double t) {
return ((x * y) - (z * y)) * t;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = ((x * y) - (z * y)) * t
end function
public static double code(double x, double y, double z, double t) {
return ((x * y) - (z * y)) * t;
}
def code(x, y, z, t): return ((x * y) - (z * y)) * t
function code(x, y, z, t) return Float64(Float64(Float64(x * y) - Float64(z * y)) * t) end
function tmp = code(x, y, z, t) tmp = ((x * y) - (z * y)) * t; end
code[x_, y_, z_, t_] := N[(N[(N[(x * y), $MachinePrecision] - N[(z * y), $MachinePrecision]), $MachinePrecision] * t), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot y - z \cdot y\right) \cdot t
\end{array}
Sampling outcomes in binary64 precision:
Herbie found 7 alternatives:
| Alternative | Accuracy | Speedup |
|---|
(FPCore (x y z t) :precision binary64 (* (- (* x y) (* z y)) t))
double code(double x, double y, double z, double t) {
return ((x * y) - (z * y)) * t;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = ((x * y) - (z * y)) * t
end function
public static double code(double x, double y, double z, double t) {
return ((x * y) - (z * y)) * t;
}
def code(x, y, z, t): return ((x * y) - (z * y)) * t
function code(x, y, z, t) return Float64(Float64(Float64(x * y) - Float64(z * y)) * t) end
function tmp = code(x, y, z, t) tmp = ((x * y) - (z * y)) * t; end
code[x_, y_, z_, t_] := N[(N[(N[(x * y), $MachinePrecision] - N[(z * y), $MachinePrecision]), $MachinePrecision] * t), $MachinePrecision]
\begin{array}{l}
\\
\left(x \cdot y - z \cdot y\right) \cdot t
\end{array}
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (if (<= t 1.8e-13) (* y (* t (- x z))) (* (- x z) (* t y))))
assert(y < t);
double code(double x, double y, double z, double t) {
double tmp;
if (t <= 1.8e-13) {
tmp = y * (t * (x - z));
} else {
tmp = (x - z) * (t * y);
}
return tmp;
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if (t <= 1.8d-13) then
tmp = y * (t * (x - z))
else
tmp = (x - z) * (t * y)
end if
code = tmp
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
double tmp;
if (t <= 1.8e-13) {
tmp = y * (t * (x - z));
} else {
tmp = (x - z) * (t * y);
}
return tmp;
}
[y, t] = sort([y, t]) def code(x, y, z, t): tmp = 0 if t <= 1.8e-13: tmp = y * (t * (x - z)) else: tmp = (x - z) * (t * y) return tmp
y, t = sort([y, t]) function code(x, y, z, t) tmp = 0.0 if (t <= 1.8e-13) tmp = Float64(y * Float64(t * Float64(x - z))); else tmp = Float64(Float64(x - z) * Float64(t * y)); end return tmp end
y, t = num2cell(sort([y, t])){:}
function tmp_2 = code(x, y, z, t)
tmp = 0.0;
if (t <= 1.8e-13)
tmp = y * (t * (x - z));
else
tmp = (x - z) * (t * y);
end
tmp_2 = tmp;
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := If[LessEqual[t, 1.8e-13], N[(y * N[(t * N[(x - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(x - z), $MachinePrecision] * N[(t * y), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
\begin{array}{l}
\mathbf{if}\;t \leq 1.8 \cdot 10^{-13}:\\
\;\;\;\;y \cdot \left(t \cdot \left(x - z\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\left(x - z\right) \cdot \left(t \cdot y\right)\\
\end{array}
\end{array}
if t < 1.7999999999999999e-13Initial program 85.7%
distribute-rgt-out--86.7%
associate-*l*94.6%
Simplified94.6%
if 1.7999999999999999e-13 < t Initial program 96.3%
distribute-rgt-out--98.1%
associate-*l*86.2%
Simplified86.2%
add-cube-cbrt85.6%
pow385.5%
Applied egg-rr85.5%
rem-cube-cbrt86.2%
*-commutative86.2%
associate-*r*94.9%
remove-double-div94.8%
div-inv94.8%
frac-2neg94.8%
metadata-eval94.8%
associate-/r/94.9%
sub-neg94.9%
distribute-neg-in94.9%
add-sqr-sqrt47.5%
sqrt-unprod59.8%
sqr-neg59.8%
sqrt-unprod22.6%
add-sqr-sqrt42.8%
add-sqr-sqrt20.2%
sqrt-unprod65.8%
sqr-neg65.8%
sqrt-unprod47.2%
add-sqr-sqrt94.9%
Applied egg-rr94.9%
Taylor expanded in y around 0 86.2%
mul-1-neg86.2%
associate-*r*94.9%
distribute-lft-neg-in94.9%
distribute-rgt-neg-out94.9%
distribute-rgt-out--80.1%
*-commutative80.1%
distribute-rgt-neg-out80.1%
cancel-sign-sub80.1%
*-commutative80.1%
distribute-rgt-neg-out80.1%
distribute-lft-neg-in80.1%
associate-*r*75.4%
mul-1-neg75.4%
associate-*r*73.5%
+-commutative73.5%
associate-*r*75.4%
mul-1-neg75.4%
associate-*r*80.1%
distribute-rgt-neg-in80.1%
distribute-lft-in94.9%
sub-neg94.9%
*-commutative94.9%
Simplified94.9%
Final simplification94.6%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (if (or (<= x -4.8e-85) (not (<= x 3.9e+25))) (* t (* y x)) (* y (* t (- z)))))
assert(y < t);
double code(double x, double y, double z, double t) {
double tmp;
if ((x <= -4.8e-85) || !(x <= 3.9e+25)) {
tmp = t * (y * x);
} else {
tmp = y * (t * -z);
}
return tmp;
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if ((x <= (-4.8d-85)) .or. (.not. (x <= 3.9d+25))) then
tmp = t * (y * x)
else
tmp = y * (t * -z)
end if
code = tmp
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
double tmp;
if ((x <= -4.8e-85) || !(x <= 3.9e+25)) {
tmp = t * (y * x);
} else {
tmp = y * (t * -z);
}
return tmp;
}
[y, t] = sort([y, t]) def code(x, y, z, t): tmp = 0 if (x <= -4.8e-85) or not (x <= 3.9e+25): tmp = t * (y * x) else: tmp = y * (t * -z) return tmp
y, t = sort([y, t]) function code(x, y, z, t) tmp = 0.0 if ((x <= -4.8e-85) || !(x <= 3.9e+25)) tmp = Float64(t * Float64(y * x)); else tmp = Float64(y * Float64(t * Float64(-z))); end return tmp end
y, t = num2cell(sort([y, t])){:}
function tmp_2 = code(x, y, z, t)
tmp = 0.0;
if ((x <= -4.8e-85) || ~((x <= 3.9e+25)))
tmp = t * (y * x);
else
tmp = y * (t * -z);
end
tmp_2 = tmp;
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := If[Or[LessEqual[x, -4.8e-85], N[Not[LessEqual[x, 3.9e+25]], $MachinePrecision]], N[(t * N[(y * x), $MachinePrecision]), $MachinePrecision], N[(y * N[(t * (-z)), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
\begin{array}{l}
\mathbf{if}\;x \leq -4.8 \cdot 10^{-85} \lor \neg \left(x \leq 3.9 \cdot 10^{+25}\right):\\
\;\;\;\;t \cdot \left(y \cdot x\right)\\
\mathbf{else}:\\
\;\;\;\;y \cdot \left(t \cdot \left(-z\right)\right)\\
\end{array}
\end{array}
if x < -4.8000000000000001e-85 or 3.9000000000000002e25 < x Initial program 84.9%
distribute-rgt-out--87.0%
Simplified87.0%
Taylor expanded in x around inf 69.2%
if -4.8000000000000001e-85 < x < 3.9000000000000002e25Initial program 92.1%
distribute-rgt-out--92.1%
associate-*l*92.8%
Simplified92.8%
Taylor expanded in x around 0 86.1%
associate-*r*86.1%
neg-mul-186.1%
Simplified86.1%
Final simplification76.4%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (if (or (<= z -2.8e+20) (not (<= z 5800.0))) (* t (* y (- z))) (* t (* y x))))
assert(y < t);
double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2.8e+20) || !(z <= 5800.0)) {
tmp = t * (y * -z);
} else {
tmp = t * (y * x);
}
return tmp;
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if ((z <= (-2.8d+20)) .or. (.not. (z <= 5800.0d0))) then
tmp = t * (y * -z)
else
tmp = t * (y * x)
end if
code = tmp
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
double tmp;
if ((z <= -2.8e+20) || !(z <= 5800.0)) {
tmp = t * (y * -z);
} else {
tmp = t * (y * x);
}
return tmp;
}
[y, t] = sort([y, t]) def code(x, y, z, t): tmp = 0 if (z <= -2.8e+20) or not (z <= 5800.0): tmp = t * (y * -z) else: tmp = t * (y * x) return tmp
y, t = sort([y, t]) function code(x, y, z, t) tmp = 0.0 if ((z <= -2.8e+20) || !(z <= 5800.0)) tmp = Float64(t * Float64(y * Float64(-z))); else tmp = Float64(t * Float64(y * x)); end return tmp end
y, t = num2cell(sort([y, t])){:}
function tmp_2 = code(x, y, z, t)
tmp = 0.0;
if ((z <= -2.8e+20) || ~((z <= 5800.0)))
tmp = t * (y * -z);
else
tmp = t * (y * x);
end
tmp_2 = tmp;
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := If[Or[LessEqual[z, -2.8e+20], N[Not[LessEqual[z, 5800.0]], $MachinePrecision]], N[(t * N[(y * (-z)), $MachinePrecision]), $MachinePrecision], N[(t * N[(y * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
\begin{array}{l}
\mathbf{if}\;z \leq -2.8 \cdot 10^{+20} \lor \neg \left(z \leq 5800\right):\\
\;\;\;\;t \cdot \left(y \cdot \left(-z\right)\right)\\
\mathbf{else}:\\
\;\;\;\;t \cdot \left(y \cdot x\right)\\
\end{array}
\end{array}
if z < -2.8e20 or 5800 < z Initial program 84.3%
distribute-rgt-out--86.7%
Simplified86.7%
Taylor expanded in x around 0 73.5%
neg-mul-173.5%
distribute-lft-neg-in73.5%
Simplified73.5%
if -2.8e20 < z < 5800Initial program 91.7%
distribute-rgt-out--91.7%
Simplified91.7%
Taylor expanded in x around inf 77.1%
Final simplification75.3%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (if (<= y -9e+106) (* y (* t (- x z))) (* t (* y (- x z)))))
assert(y < t);
double code(double x, double y, double z, double t) {
double tmp;
if (y <= -9e+106) {
tmp = y * (t * (x - z));
} else {
tmp = t * (y * (x - z));
}
return tmp;
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if (y <= (-9d+106)) then
tmp = y * (t * (x - z))
else
tmp = t * (y * (x - z))
end if
code = tmp
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
double tmp;
if (y <= -9e+106) {
tmp = y * (t * (x - z));
} else {
tmp = t * (y * (x - z));
}
return tmp;
}
[y, t] = sort([y, t]) def code(x, y, z, t): tmp = 0 if y <= -9e+106: tmp = y * (t * (x - z)) else: tmp = t * (y * (x - z)) return tmp
y, t = sort([y, t]) function code(x, y, z, t) tmp = 0.0 if (y <= -9e+106) tmp = Float64(y * Float64(t * Float64(x - z))); else tmp = Float64(t * Float64(y * Float64(x - z))); end return tmp end
y, t = num2cell(sort([y, t])){:}
function tmp_2 = code(x, y, z, t)
tmp = 0.0;
if (y <= -9e+106)
tmp = y * (t * (x - z));
else
tmp = t * (y * (x - z));
end
tmp_2 = tmp;
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := If[LessEqual[y, -9e+106], N[(y * N[(t * N[(x - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(t * N[(y * N[(x - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
\begin{array}{l}
\mathbf{if}\;y \leq -9 \cdot 10^{+106}:\\
\;\;\;\;y \cdot \left(t \cdot \left(x - z\right)\right)\\
\mathbf{else}:\\
\;\;\;\;t \cdot \left(y \cdot \left(x - z\right)\right)\\
\end{array}
\end{array}
if y < -8.9999999999999994e106Initial program 68.1%
distribute-rgt-out--73.4%
associate-*l*97.3%
Simplified97.3%
if -8.9999999999999994e106 < y Initial program 91.5%
distribute-rgt-out--92.0%
Simplified92.0%
Final simplification92.8%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (if (<= t 9.2e-38) (* y (* t x)) (* t (* y x))))
assert(y < t);
double code(double x, double y, double z, double t) {
double tmp;
if (t <= 9.2e-38) {
tmp = y * (t * x);
} else {
tmp = t * (y * x);
}
return tmp;
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if (t <= 9.2d-38) then
tmp = y * (t * x)
else
tmp = t * (y * x)
end if
code = tmp
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
double tmp;
if (t <= 9.2e-38) {
tmp = y * (t * x);
} else {
tmp = t * (y * x);
}
return tmp;
}
[y, t] = sort([y, t]) def code(x, y, z, t): tmp = 0 if t <= 9.2e-38: tmp = y * (t * x) else: tmp = t * (y * x) return tmp
y, t = sort([y, t]) function code(x, y, z, t) tmp = 0.0 if (t <= 9.2e-38) tmp = Float64(y * Float64(t * x)); else tmp = Float64(t * Float64(y * x)); end return tmp end
y, t = num2cell(sort([y, t])){:}
function tmp_2 = code(x, y, z, t)
tmp = 0.0;
if (t <= 9.2e-38)
tmp = y * (t * x);
else
tmp = t * (y * x);
end
tmp_2 = tmp;
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := If[LessEqual[t, 9.2e-38], N[(y * N[(t * x), $MachinePrecision]), $MachinePrecision], N[(t * N[(y * x), $MachinePrecision]), $MachinePrecision]]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
\begin{array}{l}
\mathbf{if}\;t \leq 9.2 \cdot 10^{-38}:\\
\;\;\;\;y \cdot \left(t \cdot x\right)\\
\mathbf{else}:\\
\;\;\;\;t \cdot \left(y \cdot x\right)\\
\end{array}
\end{array}
if t < 9.20000000000000007e-38Initial program 85.4%
distribute-rgt-out--86.5%
associate-*l*94.5%
Simplified94.5%
Taylor expanded in x around inf 56.7%
if 9.20000000000000007e-38 < t Initial program 96.5%
distribute-rgt-out--98.2%
Simplified98.2%
Taylor expanded in x around inf 47.9%
Final simplification54.6%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (* y (* t (- x z))))
assert(y < t);
double code(double x, double y, double z, double t) {
return y * (t * (x - z));
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = y * (t * (x - z))
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
return y * (t * (x - z));
}
[y, t] = sort([y, t]) def code(x, y, z, t): return y * (t * (x - z))
y, t = sort([y, t]) function code(x, y, z, t) return Float64(y * Float64(t * Float64(x - z))) end
y, t = num2cell(sort([y, t])){:}
function tmp = code(x, y, z, t)
tmp = y * (t * (x - z));
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := N[(y * N[(t * N[(x - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
y \cdot \left(t \cdot \left(x - z\right)\right)
\end{array}
Initial program 87.9%
distribute-rgt-out--89.2%
associate-*l*92.8%
Simplified92.8%
Final simplification92.8%
NOTE: y and t should be sorted in increasing order before calling this function. (FPCore (x y z t) :precision binary64 (* y (* t x)))
assert(y < t);
double code(double x, double y, double z, double t) {
return y * (t * x);
}
NOTE: y and t should be sorted in increasing order before calling this function.
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
code = y * (t * x)
end function
assert y < t;
public static double code(double x, double y, double z, double t) {
return y * (t * x);
}
[y, t] = sort([y, t]) def code(x, y, z, t): return y * (t * x)
y, t = sort([y, t]) function code(x, y, z, t) return Float64(y * Float64(t * x)) end
y, t = num2cell(sort([y, t])){:}
function tmp = code(x, y, z, t)
tmp = y * (t * x);
end
NOTE: y and t should be sorted in increasing order before calling this function. code[x_, y_, z_, t_] := N[(y * N[(t * x), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}
[y, t] = \mathsf{sort}([y, t])\\
\\
y \cdot \left(t \cdot x\right)
\end{array}
Initial program 87.9%
distribute-rgt-out--89.2%
associate-*l*92.8%
Simplified92.8%
Taylor expanded in x around inf 53.5%
Final simplification53.5%
(FPCore (x y z t) :precision binary64 (if (< t -9.231879582886777e-80) (* (* y t) (- x z)) (if (< t 2.543067051564877e+83) (* y (* t (- x z))) (* (* y (- x z)) t))))
double code(double x, double y, double z, double t) {
double tmp;
if (t < -9.231879582886777e-80) {
tmp = (y * t) * (x - z);
} else if (t < 2.543067051564877e+83) {
tmp = y * (t * (x - z));
} else {
tmp = (y * (x - z)) * t;
}
return tmp;
}
real(8) function code(x, y, z, t)
real(8), intent (in) :: x
real(8), intent (in) :: y
real(8), intent (in) :: z
real(8), intent (in) :: t
real(8) :: tmp
if (t < (-9.231879582886777d-80)) then
tmp = (y * t) * (x - z)
else if (t < 2.543067051564877d+83) then
tmp = y * (t * (x - z))
else
tmp = (y * (x - z)) * t
end if
code = tmp
end function
public static double code(double x, double y, double z, double t) {
double tmp;
if (t < -9.231879582886777e-80) {
tmp = (y * t) * (x - z);
} else if (t < 2.543067051564877e+83) {
tmp = y * (t * (x - z));
} else {
tmp = (y * (x - z)) * t;
}
return tmp;
}
def code(x, y, z, t): tmp = 0 if t < -9.231879582886777e-80: tmp = (y * t) * (x - z) elif t < 2.543067051564877e+83: tmp = y * (t * (x - z)) else: tmp = (y * (x - z)) * t return tmp
function code(x, y, z, t) tmp = 0.0 if (t < -9.231879582886777e-80) tmp = Float64(Float64(y * t) * Float64(x - z)); elseif (t < 2.543067051564877e+83) tmp = Float64(y * Float64(t * Float64(x - z))); else tmp = Float64(Float64(y * Float64(x - z)) * t); end return tmp end
function tmp_2 = code(x, y, z, t) tmp = 0.0; if (t < -9.231879582886777e-80) tmp = (y * t) * (x - z); elseif (t < 2.543067051564877e+83) tmp = y * (t * (x - z)); else tmp = (y * (x - z)) * t; end tmp_2 = tmp; end
code[x_, y_, z_, t_] := If[Less[t, -9.231879582886777e-80], N[(N[(y * t), $MachinePrecision] * N[(x - z), $MachinePrecision]), $MachinePrecision], If[Less[t, 2.543067051564877e+83], N[(y * N[(t * N[(x - z), $MachinePrecision]), $MachinePrecision]), $MachinePrecision], N[(N[(y * N[(x - z), $MachinePrecision]), $MachinePrecision] * t), $MachinePrecision]]]
\begin{array}{l}
\\
\begin{array}{l}
\mathbf{if}\;t < -9.231879582886777 \cdot 10^{-80}:\\
\;\;\;\;\left(y \cdot t\right) \cdot \left(x - z\right)\\
\mathbf{elif}\;t < 2.543067051564877 \cdot 10^{+83}:\\
\;\;\;\;y \cdot \left(t \cdot \left(x - z\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\left(y \cdot \left(x - z\right)\right) \cdot t\\
\end{array}
\end{array}
herbie shell --seed 2023185
(FPCore (x y z t)
:name "Linear.Projection:inverseInfinitePerspective from linear-1.19.1.3"
:precision binary64
:herbie-target
(if (< t -9.231879582886777e-80) (* (* y t) (- x z)) (if (< t 2.543067051564877e+83) (* y (* t (- x z))) (* (* y (- x z)) t)))
(* (- (* x y) (* z y)) t))