using System;
using System.Diagnostics;
namespace Unity.MLAgents
{
internal static class Utilities
{
///
/// Calculates the cumulative sum of an integer array. The result array will be one element
/// larger than the input array since it has a padded 0 at the beginning.
/// If the input is [a, b, c], the result will be [0, a, a+b, a+b+c]
///
///
/// Input array whose elements will be cumulatively added
///
/// The cumulative sum of the input array.
internal static int[] CumSum(int[] input)
{
var runningSum = 0;
var result = new int[input.Length + 1];
for (var actionIndex = 0; actionIndex < input.Length; actionIndex++)
{
runningSum += input[actionIndex];
result[actionIndex + 1] = runningSum;
}
return result;
}
[Conditional("DEBUG")]
internal static void DebugCheckNanAndInfinity(float value, string valueCategory, string caller)
{
if (float.IsNaN(value))
{
throw new ArgumentException($"NaN {valueCategory} passed to {caller}.");
}
if (float.IsInfinity(value))
{
throw new ArgumentException($"Inifinity {valueCategory} passed to {caller}.");
}
}
}
}