API Reference > geometry-core > Bspline > Bezier1dNd > evaluateDerivative evaluateDerivative Method Return the curve derivative value at bezier fraction s evaluateDerivative(s: number, buffer?: Float64Array): Float64Array Parameter Type Description s number buffer Float64Array Returns - Float64Array buffer of length blockSize. Defined in bspline/Bezier1dNd.ts Line 93 Last Updated: 12 June, 2024