using NumSharp;

using System;

using System.Collections.Generic;

using System.IO;

using System.Linq;

using System.Text;

namespace Bigtree.Algorithm

{

public class Utils

{

public static (NDArray, NDArray) ReadCsv(string path)

{

List<int> labels = new List<int>();

var x1 = new List<double>();

var y1 = new List<int>();

int length1d = 0;

int length2d = 0;

using (StreamReader reader = new StreamReader(path))

{

string line = String.Empty;

while (!String.IsNullOrEmpty(line = reader.ReadLine()))

{

var tokens = line.Split(',');

x1.AddRange(tokens.Select(x => double.Parse(x)).Take(tokens.Length - 1));

var _y = int.Parse(tokens[tokens.Length - 1]);

if (!labels.Contains(_y))

{

labels.Add(_y);

}

y1.Add(labels.FindIndex(l => l == _y));

length1d++;

length2d = tokens.Length - 1;

}

}

var X = np.array(x1.ToArray()).reshape(length1d, length2d);

var y = np.array(y1.ToArray());

return (X, y);

}

public static List<List<int>> CrossValFolds(int N, int n_folds)

{

var folds = new List<List<int>>();

/*var rands = np.random.permutation(N);

var N_fold = N / n_folds;

for(int i = 0; i < n_folds; i++)

{

var list = rands.Data<int>().Skip(N_fold * i).Take(N_fold).ToList();

folds.Add(list);

}*/

return folds;

}

}

}