CoRN.examples.RealFaster

Require Import BigZ CRArith ARbigD ARbigQ ARQ ARtrans ARsign.

Definition myAR := ARbigD.

Definition answer (n : positive) (r : ARbigD) : bigZ :=
 let m := iter_pos n _ (Pmult 10) 1%positive in
 let (a, b) := (approximate r (1#m)%Qpos : bigD) × 'Zpos m in
 BigZ.shiftl a b.

Definition no_answer (n : positive) (r : myAR) :=
 let m := iter_pos n _ (Pmult 10) 1%positive in let _ :=
    approximate r (1#m)%Qpos in tt.

Definition xkcd : myAR := (ARexp ARpi)-ARpi.

Time Eval vm_compute in (answer 10 xkcd).

Example xkcd217A : ARltT xkcd ('20%Z).
Proof. Time AR_solve_ltT (-8)%Z. Defined.


Time Definition P01 : myAR := ARsin (ARsin (AQsin 1)).

Time Eval vm_compute in (answer 500 P01).
Time Eval vm_compute in (no_answer 500 P01).
Definition P02 : myAR := ARsqrt (ARcompress ARpi).
Time Eval vm_compute in (answer 500 P02).

Definition P03 : myAR := ARsin (AQexp 1).
Time Eval vm_compute in (answer 500 P03).

Definition P04 : myAR := ARexp (ARcompress (ARpi × AQsqrt ('163%Z))).
Time Eval vm_compute in (answer 500 P04).

Definition P05 : myAR := ARexp (ARexp (AQexp 1)).
Time Eval vm_compute in (answer 500 P05).

Definition P07 : myAR := AQexp ('1000%Z).
Time Eval vm_compute in (answer 2000 P07).

Definition P08 : myAR := AQcos ('(10^50)%Z).
Time Eval vm_compute in (answer 2000 P08).

Definition C02_prf : ARapartT (ARpi : myAR) (0 : myAR).
Proof. AR_solve_apartT (-8)%Z. Defined.

Definition C02 : myAR := ARsqrt (AQexp 1 × ARinvT ARpi C02_prf).
Time Eval vm_compute in (answer 250 C02).

Definition C03 : myAR := ARsin (ARcompress ((AQexp 1 + 1) ^ (3:N))).
Time Eval vm_compute in (answer 500 C03).

Definition C04 : myAR := ARexp (ARcompress (ARpi × AQsqrt ('2011%Z))).
Time Eval vm_compute in (answer 500 C04).

Definition C05 : myAR := ARexp (ARexp (ARsqrt (AQexp 1))).
Time Eval vm_compute in (answer 500 C05).

Definition ARtest1 : myAR := ARpi.
Time Eval vm_compute in (answer 1500 ARtest1).

Definition ARtest2 : myAR := ARarctan (ARcompress ARpi).
Time Eval vm_compute in (answer 100 ARtest2).

Definition ARtest3 : myAR := ARsqrt 2.
Time Eval vm_compute in (answer 1000 ARtest3).

Definition ARtest4 : myAR := ARsin ARpi.
Time Eval vm_compute in (answer 500 ARtest4).