\[\left(\frac{\pi}{2.0} \cdot \frac{1.0}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1.0}{a} - \frac{1.0}{b}\right)\]

\left(\frac{\pi}{2.0} \cdot \frac{1.0}{b \cdot b - a \cdot a}\right) \cdot \left(\frac{1.0}{a} - \frac{1.0}{b}\right)

double f(double a, double b) {
        double r1087798 = atan2(1.0, 0.0);
        double r1087799 = 2.0;
        double r1087800 = r1087798 / r1087799;
        double r1087801 = 1.0;
        double r1087802 = b;
        double r1087803 = r1087802 * r1087802;
        double r1087804 = a;
        double r1087805 = r1087804 * r1087804;
        double r1087806 = r1087803 - r1087805;
        double r1087807 = r1087801 / r1087806;
        double r1087808 = r1087800 * r1087807;
        double r1087809 = r1087801 / r1087804;
        double r1087810 = r1087801 / r1087802;
        double r1087811 = r1087809 - r1087810;
        double r1087812 = r1087808 * r1087811;
        return r1087812;
}

Reproduce

Please include this information when filing a bug report:

herbie shell --seed 2019165 
(FPCore (a b)
  :name "NMSE Section 6.1 mentioned, B"
  (* (* (/ PI 2.0) (/ 1.0 (- (* b b) (* a a)))) (- (/ 1.0 a) (/ 1.0 b))))

Backtrace

->bf: contract violation expected: value? given: 'PI in: the 1st argument of (-> value? bigvalue?) contract from: (function ->bf) blaming: /data/pavpan/nightlies/herbie/optional-posits/src/float.rkt (assuming the contract is correct) at: /data/pavpan/nightlies/herbie/optional-posits/src/float.rkt:163.18		L	C
raise-blame-error16	/opt/racket-7.0/collects/racket/contract/private/blame.rkt	347	0
(unnamed)	/opt/racket-7.0/collects/racket/contract/private/arrow-higher-order.rkt	357	33
(unnamed)	/data/pavpan/nightlies/herbie/optional-posits/src/core/localize.rkt	22	13
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
loop	/opt/racket-7.0/collects/racket/private/map.rkt	40	19
parse-loop15	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
loop	/opt/racket-7.0/collects/racket/private/map.rkt	40	19
parse-loop15	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
loop	/opt/racket-7.0/collects/racket/private/map.rkt	40	19
parse-loop15	/opt/racket-7.0/collects/racket/match/compiler.rkt	418	15
hash-ref!	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	376	2
localize-error	/data/pavpan/nightlies/herbie/optional-posits/src/core/localize.rkt	52	0
localize!	/data/pavpan/nightlies/herbie/optional-posits/src/mainloop.rkt	116	0
run-iter!	/data/pavpan/nightlies/herbie/optional-posits/src/mainloop.rkt	317	0
for-loop	/data/pavpan/nightlies/herbie/optional-posits/src/mainloop.rkt	351	4
run-improve40	/data/pavpan/nightlies/herbie/optional-posits/src/mainloop.rkt	336	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28
run	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	39	2
profile-thunk16	/opt/racket-7.0/share/pkgs/profile-lib/main.rkt	9	0
(unnamed)	/opt/racket-7.0/collects/racket/private/more-scheme.rkt	261	28