Numeric.Signal.Multichannel:$cget from hsignal-0.2.7.1

Percentage Accurate: 97.7% → 97.7%
Time: 3.1s
Alternatives: 7
Speedup: 1.0×

Specification

?
\[\frac{x}{y} \cdot \left(z - t\right) + t \]
(FPCore (x y z t)
  :precision binary64
  :pre TRUE
  (+ (* (/ x y) (- z t)) t))
double code(double x, double y, double z, double t) {
	return ((x / y) * (z - t)) + t;
}
real(8) function code(x, y, z, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = ((x / y) * (z - t)) + t
end function
public static double code(double x, double y, double z, double t) {
	return ((x / y) * (z - t)) + t;
}
def code(x, y, z, t):
	return ((x / y) * (z - t)) + t
function code(x, y, z, t)
	return Float64(Float64(Float64(x / y) * Float64(z - t)) + t)
end
function tmp = code(x, y, z, t)
	tmp = ((x / y) * (z - t)) + t;
end
code[x_, y_, z_, t_] := N[(N[(N[(x / y), $MachinePrecision] * N[(z - t), $MachinePrecision]), $MachinePrecision] + t), $MachinePrecision]
f(x, y, z, t):
	x in [-inf, +inf],
	y in [-inf, +inf],
	z in [-inf, +inf],
	t in [-inf, +inf]
code: THEORY
BEGIN
f(x, y, z, t: real): real =
	((x / y) * (z - t)) + t
END code
\frac{x}{y} \cdot \left(z - t\right) + t

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 7 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 97.7% accurate, 1.0× speedup?

\[\frac{x}{y} \cdot \left(z - t\right) + t \]
(FPCore (x y z t)
  :precision binary64
  :pre TRUE
  (+ (* (/ x y) (- z t)) t))
double code(double x, double y, double z, double t) {
	return ((x / y) * (z - t)) + t;
}
real(8) function code(x, y, z, t)
use fmin_fmax_functions
    real(8), intent (in) :: x
    real(8), intent (in) :: y
    real(8), intent (in) :: z
    real(8), intent (in) :: t
    code = ((x / y) * (z - t)) + t
end function
public static double code(double x, double y, double z, double t) {
	return ((x / y) * (z - t)) + t;
}
def code(x, y, z, t):
	return ((x / y) * (z - t)) + t
function code(x, y, z, t)
	return Float64(Float64(Float64(x / y) * Float64(z - t)) + t)
end
function tmp = code(x, y, z, t)
	tmp = ((x / y) * (z - t)) + t;
end
code[x_, y_, z_, t_] := N[(N[(N[(x / y), $MachinePrecision] * N[(z - t), $MachinePrecision]), $MachinePrecision] + t), $MachinePrecision]
f(x, y, z, t):
	x in [-inf, +inf],
	y in [-inf, +inf],
	z in [-inf, +inf],
	t in [-inf, +inf]
code: THEORY
BEGIN
f(x, y, z, t: real): real =
	((x / y) * (z - t)) + t
END code
\frac{x}{y} \cdot \left(z - t\right) + t

Alternative 1: 97.7% accurate, 1.0× speedup?

\[\mathsf{fma}\left(z - t, \frac{x}{y}, t\right) \]
(FPCore (x y z t)
  :precision binary64
  :pre TRUE
  (fma (- z t) (/ x y) t))
double code(double x, double y, double z, double t) {
	return fma((z - t), (x / y), t);
}
function code(x, y, z, t)
	return fma(Float64(z - t), Float64(x / y), t)
end
code[x_, y_, z_, t_] := N[(N[(z - t), $MachinePrecision] * N[(x / y), $MachinePrecision] + t), $MachinePrecision]
f(x, y, z, t):
	x in [-inf, +inf],
	y in [-inf, +inf],
	z in [-inf, +inf],
	t in [-inf, +inf]
code: THEORY
BEGIN
f(x, y, z, t: real): real =
	((z - t) * (x / y)) + t
END code
\mathsf{fma}\left(z - t, \frac{x}{y}, t\right)
Derivation
  1. Initial program 97.7%

    \[\frac{x}{y} \cdot \left(z - t\right) + t \]
  2. Step-by-step derivation
    1. Applied rewrites97.7%

      \[\leadsto \mathsf{fma}\left(z - t, \frac{x}{y}, t\right) \]
    2. Add Preprocessing

    Alternative 2: 94.2% accurate, 0.5× speedup?

    \[\begin{array}{l} t_1 := \frac{x \cdot \left(z - t\right)}{y}\\ \mathbf{if}\;\frac{x}{y} \leq -2000000000000:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;\frac{x}{y} \leq 500000000000:\\ \;\;\;\;z \cdot \frac{x}{y} + t\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \]
    (FPCore (x y z t)
      :precision binary64
      :pre TRUE
      (let* ((t_1 (/ (* x (- z t)) y)))
      (if (<= (/ x y) -2000000000000.0)
        t_1
        (if (<= (/ x y) 500000000000.0) (+ (* z (/ x y)) t) t_1))))
    double code(double x, double y, double z, double t) {
    	double t_1 = (x * (z - t)) / y;
    	double tmp;
    	if ((x / y) <= -2000000000000.0) {
    		tmp = t_1;
    	} else if ((x / y) <= 500000000000.0) {
    		tmp = (z * (x / y)) + t;
    	} else {
    		tmp = t_1;
    	}
    	return tmp;
    }
    
    real(8) function code(x, y, z, t)
    use fmin_fmax_functions
        real(8), intent (in) :: x
        real(8), intent (in) :: y
        real(8), intent (in) :: z
        real(8), intent (in) :: t
        real(8) :: t_1
        real(8) :: tmp
        t_1 = (x * (z - t)) / y
        if ((x / y) <= (-2000000000000.0d0)) then
            tmp = t_1
        else if ((x / y) <= 500000000000.0d0) then
            tmp = (z * (x / y)) + t
        else
            tmp = t_1
        end if
        code = tmp
    end function
    
    public static double code(double x, double y, double z, double t) {
    	double t_1 = (x * (z - t)) / y;
    	double tmp;
    	if ((x / y) <= -2000000000000.0) {
    		tmp = t_1;
    	} else if ((x / y) <= 500000000000.0) {
    		tmp = (z * (x / y)) + t;
    	} else {
    		tmp = t_1;
    	}
    	return tmp;
    }
    
    def code(x, y, z, t):
    	t_1 = (x * (z - t)) / y
    	tmp = 0
    	if (x / y) <= -2000000000000.0:
    		tmp = t_1
    	elif (x / y) <= 500000000000.0:
    		tmp = (z * (x / y)) + t
    	else:
    		tmp = t_1
    	return tmp
    
    function code(x, y, z, t)
    	t_1 = Float64(Float64(x * Float64(z - t)) / y)
    	tmp = 0.0
    	if (Float64(x / y) <= -2000000000000.0)
    		tmp = t_1;
    	elseif (Float64(x / y) <= 500000000000.0)
    		tmp = Float64(Float64(z * Float64(x / y)) + t);
    	else
    		tmp = t_1;
    	end
    	return tmp
    end
    
    function tmp_2 = code(x, y, z, t)
    	t_1 = (x * (z - t)) / y;
    	tmp = 0.0;
    	if ((x / y) <= -2000000000000.0)
    		tmp = t_1;
    	elseif ((x / y) <= 500000000000.0)
    		tmp = (z * (x / y)) + t;
    	else
    		tmp = t_1;
    	end
    	tmp_2 = tmp;
    end
    
    code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[(x * N[(z - t), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]}, If[LessEqual[N[(x / y), $MachinePrecision], -2000000000000.0], t$95$1, If[LessEqual[N[(x / y), $MachinePrecision], 500000000000.0], N[(N[(z * N[(x / y), $MachinePrecision]), $MachinePrecision] + t), $MachinePrecision], t$95$1]]]
    
    f(x, y, z, t):
    	x in [-inf, +inf],
    	y in [-inf, +inf],
    	z in [-inf, +inf],
    	t in [-inf, +inf]
    code: THEORY
    BEGIN
    f(x, y, z, t: real): real =
    	LET t_1 = ((x * (z - t)) / y) IN
    		LET tmp_1 = IF ((x / y) <= (5e11)) THEN ((z * (x / y)) + t) ELSE t_1 ENDIF IN
    		LET tmp = IF ((x / y) <= (-2e12)) THEN t_1 ELSE tmp_1 ENDIF IN
    	tmp
    END code
    \begin{array}{l}
    t_1 := \frac{x \cdot \left(z - t\right)}{y}\\
    \mathbf{if}\;\frac{x}{y} \leq -2000000000000:\\
    \;\;\;\;t\_1\\
    
    \mathbf{elif}\;\frac{x}{y} \leq 500000000000:\\
    \;\;\;\;z \cdot \frac{x}{y} + t\\
    
    \mathbf{else}:\\
    \;\;\;\;t\_1\\
    
    
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 x y) < -2e12 or 5e11 < (/.f64 x y)

      1. Initial program 97.7%

        \[\frac{x}{y} \cdot \left(z - t\right) + t \]
      2. Step-by-step derivation
        1. Applied rewrites84.5%

          \[\leadsto \frac{\mathsf{fma}\left(z - t, x, t \cdot y\right)}{y} \]
        2. Taylor expanded in x around 0

          \[\leadsto \frac{t \cdot y}{y} \]
        3. Step-by-step derivation
          1. Applied rewrites28.7%

            \[\leadsto \frac{t \cdot y}{y} \]
          2. Taylor expanded in x around inf

            \[\leadsto \frac{x \cdot \left(z - t\right)}{y} \]
          3. Step-by-step derivation
            1. Applied rewrites58.6%

              \[\leadsto \frac{x \cdot \left(z - t\right)}{y} \]

            if -2e12 < (/.f64 x y) < 5e11

            1. Initial program 97.7%

              \[\frac{x}{y} \cdot \left(z - t\right) + t \]
            2. Taylor expanded in z around inf

              \[\leadsto \frac{x \cdot z}{y} + t \]
            3. Step-by-step derivation
              1. Applied rewrites72.1%

                \[\leadsto \frac{x \cdot z}{y} + t \]
              2. Step-by-step derivation
                1. Applied rewrites75.7%

                  \[\leadsto z \cdot \frac{x}{y} + t \]
              3. Recombined 2 regimes into one program.
              4. Add Preprocessing

              Alternative 3: 93.0% accurate, 0.5× speedup?

              \[\begin{array}{l} t_1 := \frac{x \cdot \left(z - t\right)}{y}\\ \mathbf{if}\;\frac{x}{y} \leq -2 \cdot 10^{-6}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;\frac{x}{y} \leq 5 \cdot 10^{-6}:\\ \;\;\;\;\mathsf{fma}\left(x, \frac{z}{y}, t\right)\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \]
              (FPCore (x y z t)
                :precision binary64
                :pre TRUE
                (let* ((t_1 (/ (* x (- z t)) y)))
                (if (<= (/ x y) -2e-6)
                  t_1
                  (if (<= (/ x y) 5e-6) (fma x (/ z y) t) t_1))))
              double code(double x, double y, double z, double t) {
              	double t_1 = (x * (z - t)) / y;
              	double tmp;
              	if ((x / y) <= -2e-6) {
              		tmp = t_1;
              	} else if ((x / y) <= 5e-6) {
              		tmp = fma(x, (z / y), t);
              	} else {
              		tmp = t_1;
              	}
              	return tmp;
              }
              
              function code(x, y, z, t)
              	t_1 = Float64(Float64(x * Float64(z - t)) / y)
              	tmp = 0.0
              	if (Float64(x / y) <= -2e-6)
              		tmp = t_1;
              	elseif (Float64(x / y) <= 5e-6)
              		tmp = fma(x, Float64(z / y), t);
              	else
              		tmp = t_1;
              	end
              	return tmp
              end
              
              code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[(x * N[(z - t), $MachinePrecision]), $MachinePrecision] / y), $MachinePrecision]}, If[LessEqual[N[(x / y), $MachinePrecision], -2e-6], t$95$1, If[LessEqual[N[(x / y), $MachinePrecision], 5e-6], N[(x * N[(z / y), $MachinePrecision] + t), $MachinePrecision], t$95$1]]]
              
              f(x, y, z, t):
              	x in [-inf, +inf],
              	y in [-inf, +inf],
              	z in [-inf, +inf],
              	t in [-inf, +inf]
              code: THEORY
              BEGIN
              f(x, y, z, t: real): real =
              	LET t_1 = ((x * (z - t)) / y) IN
              		LET tmp_1 = IF ((x / y) <= (50000000000000004090152695701565477293115691281855106353759765625e-70)) THEN ((x * (z / y)) + t) ELSE t_1 ENDIF IN
              		LET tmp = IF ((x / y) <= (-199999999999999990949622365177251737122787744738161563873291015625e-71)) THEN t_1 ELSE tmp_1 ENDIF IN
              	tmp
              END code
              \begin{array}{l}
              t_1 := \frac{x \cdot \left(z - t\right)}{y}\\
              \mathbf{if}\;\frac{x}{y} \leq -2 \cdot 10^{-6}:\\
              \;\;\;\;t\_1\\
              
              \mathbf{elif}\;\frac{x}{y} \leq 5 \cdot 10^{-6}:\\
              \;\;\;\;\mathsf{fma}\left(x, \frac{z}{y}, t\right)\\
              
              \mathbf{else}:\\
              \;\;\;\;t\_1\\
              
              
              \end{array}
              
              Derivation
              1. Split input into 2 regimes
              2. if (/.f64 x y) < -1.9999999999999999e-6 or 5.0000000000000004e-6 < (/.f64 x y)

                1. Initial program 97.7%

                  \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                2. Step-by-step derivation
                  1. Applied rewrites84.5%

                    \[\leadsto \frac{\mathsf{fma}\left(z - t, x, t \cdot y\right)}{y} \]
                  2. Taylor expanded in x around 0

                    \[\leadsto \frac{t \cdot y}{y} \]
                  3. Step-by-step derivation
                    1. Applied rewrites28.7%

                      \[\leadsto \frac{t \cdot y}{y} \]
                    2. Taylor expanded in x around inf

                      \[\leadsto \frac{x \cdot \left(z - t\right)}{y} \]
                    3. Step-by-step derivation
                      1. Applied rewrites58.6%

                        \[\leadsto \frac{x \cdot \left(z - t\right)}{y} \]

                      if -1.9999999999999999e-6 < (/.f64 x y) < 5.0000000000000004e-6

                      1. Initial program 97.7%

                        \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                      2. Step-by-step derivation
                        1. Applied rewrites92.6%

                          \[\leadsto \mathsf{fma}\left(x, \frac{z - t}{y}, t\right) \]
                        2. Taylor expanded in z around inf

                          \[\leadsto \mathsf{fma}\left(x, \frac{z}{y}, t\right) \]
                        3. Step-by-step derivation
                          1. Applied rewrites72.3%

                            \[\leadsto \mathsf{fma}\left(x, \frac{z}{y}, t\right) \]
                        4. Recombined 2 regimes into one program.
                        5. Add Preprocessing

                        Alternative 4: 72.3% accurate, 1.3× speedup?

                        \[\mathsf{fma}\left(x, \frac{z}{y}, t\right) \]
                        (FPCore (x y z t)
                          :precision binary64
                          :pre TRUE
                          (fma x (/ z y) t))
                        double code(double x, double y, double z, double t) {
                        	return fma(x, (z / y), t);
                        }
                        
                        function code(x, y, z, t)
                        	return fma(x, Float64(z / y), t)
                        end
                        
                        code[x_, y_, z_, t_] := N[(x * N[(z / y), $MachinePrecision] + t), $MachinePrecision]
                        
                        f(x, y, z, t):
                        	x in [-inf, +inf],
                        	y in [-inf, +inf],
                        	z in [-inf, +inf],
                        	t in [-inf, +inf]
                        code: THEORY
                        BEGIN
                        f(x, y, z, t: real): real =
                        	(x * (z / y)) + t
                        END code
                        \mathsf{fma}\left(x, \frac{z}{y}, t\right)
                        
                        Derivation
                        1. Initial program 97.7%

                          \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                        2. Step-by-step derivation
                          1. Applied rewrites92.6%

                            \[\leadsto \mathsf{fma}\left(x, \frac{z - t}{y}, t\right) \]
                          2. Taylor expanded in z around inf

                            \[\leadsto \mathsf{fma}\left(x, \frac{z}{y}, t\right) \]
                          3. Step-by-step derivation
                            1. Applied rewrites72.3%

                              \[\leadsto \mathsf{fma}\left(x, \frac{z}{y}, t\right) \]
                            2. Add Preprocessing

                            Alternative 5: 62.2% accurate, 0.6× speedup?

                            \[\begin{array}{l} t_1 := \frac{x \cdot z}{y}\\ \mathbf{if}\;\frac{x}{y} \leq -5 \cdot 10^{-11}:\\ \;\;\;\;t\_1\\ \mathbf{elif}\;\frac{x}{y} \leq 10^{-28}:\\ \;\;\;\;t\\ \mathbf{else}:\\ \;\;\;\;t\_1\\ \end{array} \]
                            (FPCore (x y z t)
                              :precision binary64
                              :pre TRUE
                              (let* ((t_1 (/ (* x z) y)))
                              (if (<= (/ x y) -5e-11) t_1 (if (<= (/ x y) 1e-28) t t_1))))
                            double code(double x, double y, double z, double t) {
                            	double t_1 = (x * z) / y;
                            	double tmp;
                            	if ((x / y) <= -5e-11) {
                            		tmp = t_1;
                            	} else if ((x / y) <= 1e-28) {
                            		tmp = t;
                            	} else {
                            		tmp = t_1;
                            	}
                            	return tmp;
                            }
                            
                            real(8) function code(x, y, z, t)
                            use fmin_fmax_functions
                                real(8), intent (in) :: x
                                real(8), intent (in) :: y
                                real(8), intent (in) :: z
                                real(8), intent (in) :: t
                                real(8) :: t_1
                                real(8) :: tmp
                                t_1 = (x * z) / y
                                if ((x / y) <= (-5d-11)) then
                                    tmp = t_1
                                else if ((x / y) <= 1d-28) then
                                    tmp = t
                                else
                                    tmp = t_1
                                end if
                                code = tmp
                            end function
                            
                            public static double code(double x, double y, double z, double t) {
                            	double t_1 = (x * z) / y;
                            	double tmp;
                            	if ((x / y) <= -5e-11) {
                            		tmp = t_1;
                            	} else if ((x / y) <= 1e-28) {
                            		tmp = t;
                            	} else {
                            		tmp = t_1;
                            	}
                            	return tmp;
                            }
                            
                            def code(x, y, z, t):
                            	t_1 = (x * z) / y
                            	tmp = 0
                            	if (x / y) <= -5e-11:
                            		tmp = t_1
                            	elif (x / y) <= 1e-28:
                            		tmp = t
                            	else:
                            		tmp = t_1
                            	return tmp
                            
                            function code(x, y, z, t)
                            	t_1 = Float64(Float64(x * z) / y)
                            	tmp = 0.0
                            	if (Float64(x / y) <= -5e-11)
                            		tmp = t_1;
                            	elseif (Float64(x / y) <= 1e-28)
                            		tmp = t;
                            	else
                            		tmp = t_1;
                            	end
                            	return tmp
                            end
                            
                            function tmp_2 = code(x, y, z, t)
                            	t_1 = (x * z) / y;
                            	tmp = 0.0;
                            	if ((x / y) <= -5e-11)
                            		tmp = t_1;
                            	elseif ((x / y) <= 1e-28)
                            		tmp = t;
                            	else
                            		tmp = t_1;
                            	end
                            	tmp_2 = tmp;
                            end
                            
                            code[x_, y_, z_, t_] := Block[{t$95$1 = N[(N[(x * z), $MachinePrecision] / y), $MachinePrecision]}, If[LessEqual[N[(x / y), $MachinePrecision], -5e-11], t$95$1, If[LessEqual[N[(x / y), $MachinePrecision], 1e-28], t, t$95$1]]]
                            
                            f(x, y, z, t):
                            	x in [-inf, +inf],
                            	y in [-inf, +inf],
                            	z in [-inf, +inf],
                            	t in [-inf, +inf]
                            code: THEORY
                            BEGIN
                            f(x, y, z, t: real): real =
                            	LET t_1 = ((x * z) / y) IN
                            		LET tmp_1 = IF ((x / y) <= (9999999999999999712325434616006196770329693636753639999435544334276007748447435974359365218333550728857517242431640625e-146)) THEN t ELSE t_1 ENDIF IN
                            		LET tmp = IF ((x / y) <= (-50000000000000001821609865774887078958277353279981980449520051479339599609375e-87)) THEN t_1 ELSE tmp_1 ENDIF IN
                            	tmp
                            END code
                            \begin{array}{l}
                            t_1 := \frac{x \cdot z}{y}\\
                            \mathbf{if}\;\frac{x}{y} \leq -5 \cdot 10^{-11}:\\
                            \;\;\;\;t\_1\\
                            
                            \mathbf{elif}\;\frac{x}{y} \leq 10^{-28}:\\
                            \;\;\;\;t\\
                            
                            \mathbf{else}:\\
                            \;\;\;\;t\_1\\
                            
                            
                            \end{array}
                            
                            Derivation
                            1. Split input into 2 regimes
                            2. if (/.f64 x y) < -5.0000000000000002e-11 or 9.9999999999999997e-29 < (/.f64 x y)

                              1. Initial program 97.7%

                                \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                              2. Step-by-step derivation
                                1. Applied rewrites84.5%

                                  \[\leadsto \frac{\mathsf{fma}\left(z - t, x, t \cdot y\right)}{y} \]
                                2. Taylor expanded in x around 0

                                  \[\leadsto \frac{t \cdot y}{y} \]
                                3. Step-by-step derivation
                                  1. Applied rewrites28.7%

                                    \[\leadsto \frac{t \cdot y}{y} \]
                                  2. Taylor expanded in z around inf

                                    \[\leadsto \frac{x \cdot z}{y} \]
                                  3. Step-by-step derivation
                                    1. Applied rewrites37.2%

                                      \[\leadsto \frac{x \cdot z}{y} \]

                                    if -5.0000000000000002e-11 < (/.f64 x y) < 9.9999999999999997e-29

                                    1. Initial program 97.7%

                                      \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                                    2. Taylor expanded in x around 0

                                      \[\leadsto t \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites37.8%

                                        \[\leadsto t \]
                                    4. Recombined 2 regimes into one program.
                                    5. Add Preprocessing

                                    Alternative 6: 37.8% accurate, 13.0× speedup?

                                    \[t \]
                                    (FPCore (x y z t)
                                      :precision binary64
                                      :pre TRUE
                                      t)
                                    double code(double x, double y, double z, double t) {
                                    	return t;
                                    }
                                    
                                    real(8) function code(x, y, z, t)
                                    use fmin_fmax_functions
                                        real(8), intent (in) :: x
                                        real(8), intent (in) :: y
                                        real(8), intent (in) :: z
                                        real(8), intent (in) :: t
                                        code = t
                                    end function
                                    
                                    public static double code(double x, double y, double z, double t) {
                                    	return t;
                                    }
                                    
                                    def code(x, y, z, t):
                                    	return t
                                    
                                    function code(x, y, z, t)
                                    	return t
                                    end
                                    
                                    function tmp = code(x, y, z, t)
                                    	tmp = t;
                                    end
                                    
                                    code[x_, y_, z_, t_] := t
                                    
                                    f(x, y, z, t):
                                    	x in [-inf, +inf],
                                    	y in [-inf, +inf],
                                    	z in [-inf, +inf],
                                    	t in [-inf, +inf]
                                    code: THEORY
                                    BEGIN
                                    f(x, y, z, t: real): real =
                                    	t
                                    END code
                                    t
                                    
                                    Derivation
                                    1. Initial program 97.7%

                                      \[\frac{x}{y} \cdot \left(z - t\right) + t \]
                                    2. Taylor expanded in x around 0

                                      \[\leadsto t \]
                                    3. Step-by-step derivation
                                      1. Applied rewrites37.8%

                                        \[\leadsto t \]
                                      2. Add Preprocessing

                                      Reproduce

                                      ?
                                      herbie shell --seed 2026092 
                                      (FPCore (x y z t)
                                        :name "Numeric.Signal.Multichannel:$cget from hsignal-0.2.7.1"
                                        :precision binary64
                                        (+ (* (/ x y) (- z t)) t))