\[\left(10^{-5} \leq u \land u \leq 1\right) \land \left(0 \leq v \land v \leq 109.746574\right)\]

\[1 + v \cdot \log \left(u + \left(1 - u\right) \cdot e^{\frac{-2}{v}}\right) \]

(FPCore (u v)
 :precision binary32
 (+ 1.0 (* v (log (+ u (* (- 1.0 u) (exp (/ -2.0 v))))))))

float code(float u, float v) {
	return 1.0f + (v * logf((u + ((1.0f - u) * expf((-2.0f / v))))));
}

real(4) function code(u, v)
    real(4), intent (in) :: u
    real(4), intent (in) :: v
    code = 1.0e0 + (v * log((u + ((1.0e0 - u) * exp(((-2.0e0) / v))))))
end function

function code(u, v)
	return Float32(Float32(1.0) + Float32(v * log(Float32(u + Float32(Float32(Float32(1.0) - u) * exp(Float32(Float32(-2.0) / v)))))))
end

function tmp = code(u, v)
	tmp = single(1.0) + (v * log((u + ((single(1.0) - u) * exp((single(-2.0) / v))))));
end

1 + v \cdot \log \left(u + \left(1 - u\right) \cdot e^{\frac{-2}{v}}\right)

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2022204 
(FPCore (u v)
  :name "HairBSDF, sample_f, cosTheta"
  :precision binary32
  :pre (and (and (<= 1e-5 u) (<= u 1.0)) (and (<= 0.0 v) (<= v 109.746574)))
  (+ 1.0 (* v (log (+ u (* (- 1.0 u) (exp (/ -2.0 v))))))))

Backtrace

nan?: contract violation expected: real? given: 0.5000000000000001+0.8660254037844386i		L	C
simplify-node*	/data/pavpan/nightlies/herbie/fix-inf-exact/src/core/reduce.rkt	61	0
hash-ref!	/usr/share/racket/collects/racket/private/more-scheme.rkt	377	2
hash-ref!	/usr/share/racket/collects/racket/private/more-scheme.rkt	377	2
loop	.../private/map.rkt	40	19
f28	.../match/compiler.rkt	548	40
hash-ref!	/usr/share/racket/collects/racket/private/more-scheme.rkt	377	2
approximate	/data/pavpan/nightlies/herbie/fix-inf-exact/src/core/taylor.rkt	7	0
taylor-expr	/data/pavpan/nightlies/herbie/fix-inf-exact/src/patch.rkt	78	0
taylor-alt	/data/pavpan/nightlies/herbie/fix-inf-exact/src/patch.rkt	85	0
gen-series!	/data/pavpan/nightlies/herbie/fix-inf-exact/src/patch.rkt	101	0
patch-table-run	/data/pavpan/nightlies/herbie/fix-inf-exact/src/patch.rkt	310	0
(unnamed)	/usr/share/racket/collects/racket/contract/private/arrow-val-first.rkt	486	18
run-iter!	/data/pavpan/nightlies/herbie/fix-inf-exact/src/mainloop.rkt	242	0
mutate!	/data/pavpan/nightlies/herbie/fix-inf-exact/src/mainloop.rkt	348	0
run-improve!	/data/pavpan/nightlies/herbie/fix-inf-exact/src/mainloop.rkt	296	0
(unnamed)	/data/pavpan/nightlies/herbie/fix-inf-exact/src/sandbox.rkt	55	6
(unnamed)	/usr/share/racket/pkgs/profile-lib/main.rkt	40	10
profile-thunk	/usr/share/racket/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/usr/share/racket/collects/racket/engine.rkt	42	24