/// <summary>
/// Threshold phase
/// </summary>
/// <param name="definition">Aggregation Definition</param>
/// <param name="observations">Observations</param>
private void Thresholding(AggrConfig definition, IEnumerable<IObservation> observations)
{
var mean = observations.Select(e => e.Value).DefaultIfEmpty(0).Average();
var q2 = observations.Select(e => e.Value * e.Value).DefaultIfEmpty(0).Average();
int n = observations.Count();
var std = q2 / n - mean * mean;
//-----------------
//THRESHOLDING
//-----------------
//If not thresholding required return mean
if (definition.Threshold)
{
//Set threshold based on threshold type and value
var threshold = definition.ThresholdValue;
if (definition.ThresholdType == "std")
{
threshold = mean + definition.ThresholdValue * std;
}
//New observation timestamp
foreach (var obs in observations)
{
obs.Value = (obs.Value > threshold) ? 1.0 : 0.0;
}
}
}
/// <summary>
/// Load Aggregation Definition from file
/// </summary>
/// <param name="file">Input file</param>
/// <returns>Aggregation Configuration Model <see cref="AggrConfig"/> </returns>
public static AggrConfig LoadFromFile(string file)
{
AggrConfig ret = null;
StreamReader fstr = null;
JsonTextReader reader = null;
try
{
fstr = new StreamReader(file);
reader = new JsonTextReader(fstr);
JsonSerializer serializer = new JsonSerializer();
ret = serializer.Deserialize <AggrConfig>(reader);
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (reader != null)
{
reader.Close();
}
if (fstr != null)
{
fstr.Dispose();
}
}
return(ret);
}
/// <summary>
/// Day Aggregation
/// </summary>
/// <param name="definition">Aggregation Definition</param>
/// <param name="patientId">Patient Id</param>
/// <param name="observations">Observations</param>
/// <returns></returns>
private IEnumerable<IObservation> PerformDayAggregation(AggrConfig definition, string patientId, IEnumerable<PDObservation> observations)
{
// Get Min and Max Date
var minT = observations.Select(e => e.Timestamp).DefaultIfEmpty().Min();
var maxT = observations.Select(e => e.Timestamp).DefaultIfEmpty().Max();
List<IObservation> metaObservations = new List<IObservation>();
var startDate = DateTimeExtensions.FromUnixTimestampMilli(minT);
var endDate = DateTimeExtensions.FromUnixTimestampMilli(maxT);
var startT = new DateTime(startDate.Year, startDate.Month, startDate.Day, 0, 0, 0, DateTimeKind.Utc).ToUnixTimestampMilli();
var endT = new DateTime(endDate.Year, endDate.Month, endDate.Day, 23, 59, 59, DateTimeKind.Utc).ToUnixTimestampMilli();
//Estimate mean and descriptive statistics
for (long i = startT; i < endT; i += dayInterval)
{
double v = definition.Beta;
foreach (var c in definition.Variables)
{
var v1 = c.Weight * observations.Where(e => e.CodeId == c.Code&& e.Timestamp >= i && e.Timestamp < i + dayInterval).Select(e => e.Value).DefaultIfEmpty().Average();
v += v1;
}
metaObservations.Add(new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = i, Value = v });
}
return metaObservations;
}
/// <summary>
/// Save Aggregation Definition to file
/// </summary>
/// <param name="definition">Aggregation Definition Model <see cref="AggrConfig"/></param>
/// <param name="file">File to save the definition</param>
public static void SaveToFile(AggrConfig definition, string file)
{
StreamWriter fstr = null;
JsonTextWriter writer = null;
try
{
fstr = new StreamWriter(file);
writer = new JsonTextWriter(fstr);
JsonSerializer serializer = new JsonSerializer();
serializer.Serialize(writer, definition);
}
catch (Exception ex)
{
throw ex;
}
finally
{
if (writer != null)
{
writer.Close();
}
if (fstr != null)
{
fstr.Dispose();
}
}
}
/// <summary>
/// Time Aggregation
/// </summary>
/// <param name="definition">Aggregation Definition</param>
/// <param name="patientId">Patient Id</param>
/// <param name="observations">Observations</param>
/// <returns>List of observations</returns>
private IEnumerable<IObservation> PerformTimeAggregation(AggrConfig definition, string patientId, IEnumerable<PDObservation> observations)
{
List<IObservation> metaObservations = new List<IObservation>();
var minT = observations.Select(e => e.Timestamp).DefaultIfEmpty().Min();
var maxT = observations.Select(e => e.Timestamp).DefaultIfEmpty().Max();
var startDate = DateTimeExtensions.FromUnixTimestampMilli(minT);
var endDate = DateTimeExtensions.FromUnixTimestampMilli(maxT);
var t0= new DateTime(startDate.Year, startDate.Month, startDate.Day, 0, 0, 0, DateTimeKind.Utc).ToUnixTimestampMilli();
var tmax = new DateTime(endDate.Year, endDate.Month, endDate.Day, 23, 59, 59, DateTimeKind.Utc).ToUnixTimestampMilli();
for (long j = 0; j <= dayInterval; j += timeInterval)
{
double m = 0;
int n0 = 0;
double v = definition.Beta;
foreach (var c in definition.Variables)
{
n0 = 0;
m = 0;
for (long i = t0; i <= tmax; i += dayInterval)
{
long te = i + j + timeInterval;
long ts = i + j;
m += observations.Where(e => e.Timestamp >= ts && e.Timestamp < te&&e.CodeId==c.Code).Select(e => e.Value).DefaultIfEmpty(0).Sum();
n0 += observations.Where(e => e.Timestamp >= ts && e.Timestamp < te && e.CodeId == c.Code).Count();
}
if (n0 > 0)
{
v +=( m/n0) * c.Weight;
}
}
if (n0 > 0)
{
metaObservations.Add(new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = j, Value = v, Weight = n0 });
}
}
return metaObservations;
}
/// <summary>
/// PerformAggregation Aggregation
/// </summary>
/// <param name="definition">Aggregation Definition</param>
/// <param name="patientId">Patient Id</param>
/// <param name="timestamp">Timestamp</param>
/// <param name="observations">Observations</param>
/// <returns>List of observations</returns>
private IEnumerable<IObservation> PerformAggregation(AggrConfig definition, string patientId, long timestamp, IEnumerable<PDObservation> observations)
{
//-----------------
// 1st Level Aggregation
//------------
IEnumerable<IObservation> metaObservations = null;
//return PerformTotalAggregation(definition, patientId, timestamp, observations);
if (definition.AggregationType == TimeAggregationType)
{
metaObservations= PerformTimeAggregation(definition, patientId, observations);
}
else if (definition.AggregationType == DayAggregationType)
{
metaObservations= PerformDayAggregation(definition, patientId, observations);
}
else
{
metaObservations= PerformTotalAggregation(definition, patientId, timestamp, observations);
}
if(metaObservations==null)
{
//Something wrong happened!!
throw new Exception();
}
//---------------------
//Threshold meta-observations
//---------------------
Thresholding(definition, metaObservations);
//---------------------
//2nd Level aggregation
//---------------------
return MetaAggregation(definition, patientId, metaObservations);
}
/// <summary>
/// Total Aggregation
/// </summary>
/// <param name="definition">Aggregation definition</param>
/// <param name="patientId">Patient Id</param>
/// <param name="timestamp">Timestamp</param>
/// <param name="observations">Input Observations</param>
/// <returns>List of output observations</returns>
private IEnumerable<IObservation> PerformTotalAggregation(AggrConfig definition,string patientId,long timestamp,IEnumerable<PDObservation> observations)
{
double v = definition.Beta;
foreach (var c in definition.Variables)
{
var v1 = c.Weight * observations.Where(e=>e.CodeId==c.Code).Select(e => e.Value).DefaultIfEmpty().Average();
v += v1;
}
return new List<IObservation>() { new PDObservation() { Value = v, PatientId = patientId, CodeId = definition.Code, Timestamp = timestamp } };
}
private AggrConfig LoadAggrDefinition(string name)
{
return AggrConfig.LoadFromFile(name);
}
/// <summary>
/// 2nd Level Aggregation
/// </summary>
/// <param name="definition">Aggregation Definition</param>
/// <param name="patientId">Patient Id</param>
/// <param name="metaObservations">Observations</param>
/// <returns>List of observations</returns>
private IEnumerable<IObservation> MetaAggregation(AggrConfig definition, string patientId, IEnumerable<IObservation> metaObservations)
{
var endT = metaObservations.Select(e => e.Timestamp).DefaultIfEmpty().Max();
if (definition.MetaAggregationType == "sum")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Sum() } };
}
else if (definition.MetaAggregationType == "average")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Average() } };
}
else if (definition.MetaAggregationType == "mfi")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * (metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Max()- metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Average()) } };
}
else if (definition.MetaAggregationType == "count")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * metaObservations.Count() } };
}
else if (definition.MetaAggregationType == "max")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Max() } };
}
else if (definition.MetaAggregationType == "min")
{
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Min() } };
}
else if (definition.MetaAggregationType == "std")
{
var fmean = metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Average();
var fq2 = metaObservations.Select(e => e.Value * e.Value).DefaultIfEmpty(0).Average();
int fn = metaObservations.Count();
var fstd = fq2 / fn - fmean * fmean;
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value = definition.MetaScale * fstd } };
}
else if (definition.MetaAggregationType == "cv")
{
var fmean = metaObservations.Select(e => e.Value).DefaultIfEmpty(0).Average();
var fq2 = metaObservations.Select(e => e.Value * e.Value).DefaultIfEmpty(0).Average();
int fn = metaObservations.Count();
var fstd = fq2 / fn - fmean * fmean;
return new List<IObservation>() { new PDObservation() { CodeId = definition.Code, PatientId = patientId, Timestamp = endT, Value =definition.MetaScale*100*fstd/fmean } };
}
else
{
return metaObservations;
}
}
/// <summary>
/// Run Aggregation
/// This method
/// 1) loads the aggregation definition
/// 2) Fetch all required observations using the DataProxy
/// 3) Calls the PerformAggregation method to perform the aggregation and returns a new observation
///
/// </summary>
/// <param name="patientId">Patient Id</param>
/// <param name="code">Meta observation Code</param>
/// <param name="lastExecutionTime">Last execution time</param>
/// <param name="aggregationType">Overrides the default aggregation type</param>
/// <param name="filterType">Overrides the default filter type</param>
/// <returns>List of observations</returns>
public async Task<IEnumerable<IObservation>> Run(string patientId, string code, DateTime? lastExecutionTime,string aggregationType=null,string filterType=null)
{
if (patientId == null)
{
throw new ArgumentNullException(nameof(patientId));
}
if (code == null)
{
throw new ArgumentNullException(nameof(code));
}
// Get Definition File Name from AggrDefinitionDictionary
if (_definition == null)
_definition = AggrConfig.FromString(_aggrDefinitionDictionary.GetJsonConfigFromCode(code));
if (_definition == null)
{
throw new AggrDefinitionNotFoundException(nameof(_definition));
}
if(!string.IsNullOrEmpty(aggregationType))
{
_definition.AggregationType = aggregationType;
}
if (!string.IsNullOrEmpty(filterType))
{
_definition.MetaAggregationType = filterType;
}
var lastExecutionTimeStamp = lastExecutionTime.HasValue ? lastExecutionTime.Value.ToUnixTimestamp() * 1000 : 0;
//Get Data
List<PDObservation> observations = new List<PDObservation>();
foreach (var c in _definition.Variables)
{
try
{
//Get Observations For patient
var ret = await _proxy.Get<PDObservation>( MAXTAKE, 0, GetFilter(patientId, c.Code, lastExecutionTimeStamp, _definition.AggregationType), null);
observations.AddRange(ret);
}
catch (Exception ex)
{
_logger?.LogError(ex, "Error in aggregation");
}
}
var metaObservation = PerformAggregation(_definition, patientId, lastExecutionTimeStamp, observations);
return metaObservation;
}
/// <summary>
/// Create Aggregation Definition from string
/// </summary>
/// <param name="configJson">Config in json</param>
/// <returns>Aggregation Configuration Model <see cref="AggrConfig"/></returns>
public static AggrConfig FromString(string configJson)
{
AggrConfig ret = null;
return(ret = JsonConvert.DeserializeObject <AggrConfig>(configJson));
}
