// polynomial for approximating erfc(x)*exp(x*x)
//
// Copyright (c) 2022-2023, Arm Limited.
// SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception

deg = 12; // poly degree

// interval bounds
a = 0x1.60dfc14636e2ap0;
b = 0x1.d413cccfe779ap0;

f = proc(y) {
  t = y + a;
  return erfc(t) * exp(t*t);
};

poly = remez(f(x), deg, [0;b-a], 1, 1e-16);

display = hexadecimal;
print("rel error:", accurateinfnorm(1-poly(x)/f(x), [a;b], 30));
print("in [",a,b,"]");
print("coeffs:");
for i from 0 to deg do round(coeff(poly,i), 52, RN);