public void CalculateGroupsTest2()
{
double[] bytes = new[] { 1.0, 2.0, 3.0, 4.0 };
DataRow target = new DataRow(bytes);
int level = 2;
List<DataGroup> expected = new List<DataGroup>() { new DataGroup() { 5.0 }, new DataGroup() { -2.0 }, new DataGroup() { -1.0 }, new DataGroup() { 0.0 } };
List<DataGroup> actual = target.CalculateTransformedGroups(level);
for (int i = 0; i < expected.Count; i++)
{
Assert.IsTrue(actual[i] != expected[i]);
}
}
public void CalculateGroupsTestPerformace()
{
var bytes = Enumerable.Repeat(128.0, 800).ToList();
var levels = Math.Log(800, 2.0);
var rowLen = this.CalculateRowLength(levels);
while (bytes.Count() < rowLen)
{
bytes.Add(0x00);
}
var target = new DataRow(bytes.ToArray());
var sw = Stopwatch.StartNew();
target.CalculateTransformedGroups(Convert.ToInt32(levels));
sw.Stop();
Assert.IsTrue(sw.Elapsed < TimeSpan.FromSeconds(1));
}
/// <summary>
/// Retransforms this instance.
/// </summary>
/// <returns></returns>
public DataMatrix Retransform(int levelCount)
{
var matrix = new DataMatrix(MatrixType.Retransformed, this.ColumnCount);
foreach (DataRow row in this.Rows)
{
int halfGroupCount = this.ColumnCount;
var tmpRow = row.RowValues.ToArray();
for (int currentLevel = 0; currentLevel < levelCount; currentLevel++)
{
halfGroupCount = halfGroupCount / 2;
int groupLen = Convert.ToInt32(Math.Pow(2.0, currentLevel));
for (int j = 0; j < halfGroupCount; j++)
{
var r = tmpRow.ToList().ToArray();
var s = tmpRow.ToList().ToArray();
var groupOffset = (this.ColumnCount * j) / halfGroupCount;
for (int i = 0; i < groupLen; i++)
{
var a = tmpRow[groupOffset + i];
var d = tmpRow[groupOffset + groupLen + i];
r[i] = (a + d) / Math.Sqrt(2.0);
s[i] = (a - d) / Math.Sqrt(2.0);
// r[i] = (tmpRow[p + i] + tmpRow[p + h + i]) / Math.Sqrt(2.0);
// s[i] = (tmpRow[p + i] - tmpRow[p + h + i]) / Math.Sqrt(2.0);
}
for (int i = 0; i < groupLen; i++)
{
tmpRow[groupOffset + (2 * i)] = r[i];
tmpRow[groupOffset + (2 * i) + 1] = s[i];
}
}
}
for (int i = 0; i < tmpRow.Count(); i++)
{
tmpRow[i] = Math.Round(tmpRow[i], 0);
}
var nr = new DataRow(tmpRow);
matrix.Rows.Add(nr);
}
return matrix;
}
