/// <summary>
/// Draws a random sample from a group of observations, without repetitions.
/// </summary>
///
/// <typeparam name="T">The type of the observations.</typeparam>
///
/// <param name="values">The observation vector.</param>
/// <param name="size">The size of the sample to be drawn (how many samples to get).</param>
///
/// <returns>A vector containing the samples drawn from <paramref name="values"/>.</returns>
///
public static T[] Sample <T>(T[] values, int size)
{
int[] idx = Vector.Sample(size);
return(values.Submatrix(idx));
}
/// <summary>
/// Draws a random sample from a group of observations, without repetitions.
/// </summary>
///
/// <typeparam name="T">The type of the observations.</typeparam>
///
/// <param name="values">The observation vector.</param>
/// <param name="size">The size of the sample to be drawn (how many samples to get).</param>
///
/// <returns>A vector containing the samples drawn from <paramref name="values"/>.</returns>
///
public static T[] Sample <T>(this T[] values, int size)
{
int[] idx = Vector.Sample(size, values.Length);
System.Diagnostics.Debug.Assert(idx.Length == size);
return(values.Get(idx));
}
/// <summary>
/// Draws a random sample from a group of observations, with or without repetitions.
/// </summary>
///
/// <typeparam name="T">The type of the observations.</typeparam>
///
/// <param name="values">The observation vector.</param>
/// <param name="size">The size of the sample to be drawn (how many samples to get).</param>
/// <param name="replacement">Whether to sample with replacement (repeating values) or without replacement (non-repeating values).</param>
///
/// <returns>A vector containing the samples drawn from <paramref name="values"/>.</returns>
///
public static T[] Sample <T>(this T[] values, int size, bool replacement = false)
{
int[] idx = replacement ? Vector.Random(size, 0, values.Length) : Vector.Sample(size, values.Length);
System.Diagnostics.Debug.Assert(idx.Length == size);
return(values.Get(idx));
}
