Fast and stable global interpolation based on equidistant points

Abstract: This paper presents the symmetric wave interpolation method for stable global interpolation using readily available equidistant points. Its key achievement is the integration of the practical utility of such points with the numerical stability of Chebyshev interpolation. Experimental results demonstrate that symmetric wave interpolation effectively suppresses the Runge phenomenon and, crucially, delivers accuracy that matches or even surpasses Chebyshev interpolation. This work thereby provides a robust and practical solution that bridges the long-standing gap between point accessibility and numerical stability in global interpolation.