\[\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}\]

\frac{\left(-b\right) + \sqrt{b \cdot b - 4 \cdot \left(a \cdot c\right)}}{2 \cdot a}

(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))

double code(double a, double b, double c) {
	return (-b + sqrt((b * b) - (4.0 * (a * c)))) / (2.0 * a);
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2021096 
(FPCore (a b c)
  :name "quadp (p42, positive)"
  :precision binary64

  :herbie-target
  (if (< b 0.0) (/ (+ (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)) (/ c (* a (/ (- (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))))

  (/ (+ (- b) (sqrt (- (* b b) (* 4.0 (* a c))))) (* 2.0 a)))

Backtrace

...src/sampling.rkt:193:4: arity mismatch; the expected number of arguments does not match the given number expected: 1 given: 0		L	C
loop	/data/pavpan/nightlies/herbie/test-filtered-on-examples/src/points.rkt	100	4
prepare-points	/data/pavpan/nightlies/herbie/test-filtered-on-examples/src/points.rkt	131	0
run-improve	/data/pavpan/nightlies/herbie/test-filtered-on-examples/src/mainloop.rkt	395	0
(unnamed)	/data/pavpan/nightlies/herbie/test-filtered-on-examples/src/sandbox.rkt	54	6
run	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk	/opt/racket-7.9/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.9/collects/racket/engine.rkt	42	24