public static float DeNormalize(this float val, AttributeNormalizationLog normalization_log)
{
float ToReturn = val;
//Turn it into a percentage
ToReturn = (ToReturn - normalization_log.AppliedFloor) / (normalization_log.AppliedCeiling - normalization_log.AppliedFloor);
//Turn it back into a value
ToReturn = normalization_log.RawMinimumValue + ((normalization_log.RawMaximumValue - normalization_log.RawMinimumValue) * ToReturn);
return(ToReturn);
}
public static AttributeNormalizationLog NormalizeAttribute(this DataSet ds, string attribute_name, float floor = -1f, float ceiling = 1f)
{
AttributeNormalizationLog ToReturn = new AttributeNormalizationLog();
ToReturn.AttributeName = attribute_name;
//Get the raw data min and max
float RawMin = float.MaxValue;
float RawMax = float.MinValue;
foreach (DataRecord dr in ds.Records)
{
DataAttribute da = null;
try
{
da = dr.GetDataAttribute(attribute_name);
}
catch
{
}
if (da != null)
{
float val;
try
{
val = Convert.ToSingle(da.Value);
}
catch
{
throw new Exception("Unable to convert value '" + da.Value + "' of attribute '" + attribute_name + "' to a float value.");
}
RawMin = Math.Min(RawMin, val);
RawMax = Math.Max(RawMax, val);
}
}
if (RawMin == float.MaxValue && RawMax == float.MinValue)
{
throw new Exception("Unable to find max and min value for attribute type '" + attribute_name + "'.");
}
ToReturn.RawMaximumValue = RawMax;
ToReturn.RawMinimumValue = RawMin;
//Make the conversions
foreach (DataRecord dr in ds.Records)
{
DataAttribute da = null;
try
{
da = dr.GetDataAttribute(attribute_name);
}
catch
{
}
if (da != null)
{
float val = 0;
bool Continue = true;
try
{
val = Convert.ToSingle(da.Value);
}
catch
{
Continue = false;
}
if (Continue)
{
//First get as a percentage
val = (val - RawMin) / (RawMax - RawMin);
//Then apply the asked for scaling
val = floor + ((ceiling - floor) * val);
//Set the value
da.Value = val.ToString();
}
}
}
ToReturn.AppliedFloor = floor;
ToReturn.AppliedCeiling = ceiling;
return(ToReturn);
}