Can NumSharp fit polynomial surface equations?

[liyu3519]

Can NumSharp fit polynomial surface equations?

[Nucs]

@liyu3519, yes. 1-D fitting is np.polyfit, and for a polynomial surface you build the design matrix and solve with np.linalg.lstsq (0.70.0, #628):

// z = 1 + 2*x + 3*y  ->  design columns [1, x, y]
var A = np.array(new[,] { {1.0, 0, 0}, {1, 1, 0}, {1, 0, 1}, {1, 1, 1} });
var z = np.array(new[] {1.0, 3, 4, 6});

var coeffs = np.linalg.lstsq(A, z).Solution;
Console.WriteLine(coeffs);   // [1. 2. 3.]

Requires NumSharp.Interop.OpenBLAS (dotnet add package NumSharp.Interop.OpenBLAS). Closing.