xref: /aosp_15_r20/external/arm-optimized-routines/pl/math/tools/tan.sollya (revision 412f47f9e737e10ed5cc46ec6a8d7fa2264f8a14)
1*412f47f9SXin Li// polynomial for approximating double precision tan(x)
2*412f47f9SXin Li//
3*412f47f9SXin Li// Copyright (c) 2023, Arm Limited.
4*412f47f9SXin Li// SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
5*412f47f9SXin Li
6*412f47f9SXin Lideg = 8;
7*412f47f9SXin Li
8*412f47f9SXin Li// interval bounds
9*412f47f9SXin Lia = 0x1.0p-126;
10*412f47f9SXin Lib = pi / 8;
11*412f47f9SXin Li
12*412f47f9SXin Lidisplay = hexadecimal;
13*412f47f9SXin Li
14*412f47f9SXin Lif = (tan(sqrt(x))-sqrt(x))/x^(3/2);
15*412f47f9SXin Lipoly = fpminimax(f, deg, [|double ...|], [a*a;b*b]);
16*412f47f9SXin Li
17*412f47f9SXin Li//print("rel error:", accurateinfnorm(1-poly(x)/f(x), [a;b], 30));
18*412f47f9SXin Liprint("in [",a,b,"]");
19*412f47f9SXin Liprint("coeffs:");
20*412f47f9SXin Lifor i from 0 to deg do coeff(poly,i);
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