using NumSharp.Core;

using System;

using System.Collections.Generic;

using System.Text;

namespace NumSharp.Core.Sparse

{

public class spmatrix

{

public static matrix sum(_cs_matrix mx, int? axis = null, Type dtype = null)

{

var (m, n) = mx.shape.BiShape;

matrix ret = null;

// sum over columns

if (axis == 0)

{

var matrix = np.asmatrix(np.ones(new Shape(1, m), dtype));

ret = matrix * mx;

}

return ret;

}

public static void csc_matvec(int n_row, int n_col, int[] Ap, int[] Ai, double[] Ax, double[] Xx, NDArray Yx)

{

for (int j = 0; j < n_col; j++)

{

int col_start = Ap[j];

int col_end = Ap[j + 1];

for (int ii = col_start; ii < col_end; ii++)

{

int i = Ai[ii];

Yx.Data<double>()[i] += Ax[ii] * Xx[j];

}

}

}

}

}