Coefficients of minimax polynomial approximation of exp2(x) using the Remez Exchange Algorithm in range (0.0, 1.0]

approx_exp2.c

// maximum relative error : 2.38418579e-07
const float exp2_c0 = 0.999999930f;
const float exp2_c1 = 0.693153100f;
const float exp2_c2 = 0.240153617f;
const float exp2_c3 = 0.055826318f;
const float exp2_c4 = 0.008989340f;
const float exp2_c5 = 0.0018775767f;

inline float exp2_zero_one_range(float x)
{
    const float x2 = x * x;
    const float poly0 = exp2_c1 * x + exp2_c0;
    const float poly1 = exp2_c3 * x + exp2_c2;
    const float poly2 = exp2_c5 * x + exp2_c4;
    const float x4 = x2 * x2;
    return poly2 * x4 + (poly1 * x2 + poly0);
}