/// <summary>
/// This method obtains the data from the GAMS file using the low level API
/// </summary>
/// <param name="_source"></param>
/// <param name="file"></param>
/// <param name="table"></param>
/// <param name="where"></param>
/// <returns></returns>
public static IEnumerable <QvxDataRow> GetGamsDataLowLevel(string _source, string file, QvxTable table, List <string> selectedFields, List <QueryExtractor.WhereCondition> where)
{
const int GMS_VAL_LEVEL = 0;
const int GMS_VAL_MARGINAL = 1;
const int GMS_VAL_LOWER = 2;
const int GMS_VAL_UPPER = 3;
const int GMS_VAL_SCALE = 4;
//const int GMS_VAL_MAX = 5;
string msg = string.Empty, VarName = string.Empty, sText = string.Empty, UelName = string.Empty;
int ErrNr = 0, SymNr = 0, SymTyp = 0, ADim = 0, ACount = 0, AUser = 0, NRec = 0, FDim = 0, j = 0, i = 0, IDum = 0;
using (gdxcs gdx = new gdxcs(ref msg))
{
gdx.gdxOpenRead(_source + "\\" + file, ref ErrNr);
gdx.gdxFindSymbol(table.TableName, ref SymNr);
gdx.gdxSymbolInfo(SymNr, ref VarName, ref ADim, ref SymTyp);
gdx.gdxSymbolInfoX(SymNr, ref ACount, ref AUser, ref sText);
gdx.gdxDataReadRawStart(SymNr, ref NRec);
Dictionary <int, string>[] dimensionCache = new Dictionary <int, string> [ADim];
if (where.Count == 0)
{
// No WHERE clause
double[] Vals = new double[gamsglobals.val_max];
int[] Keys = new int[gamsglobals.maxdim];
while (gdx.gdxDataReadRaw(ref Keys, ref Vals, ref FDim) != 0)
{
QvxDataRow row = mapRow(Keys, Vals);
if (row != null)
{
yield return(row);
}
}
}
else
{
// WHERE clause
string[] strFilter = Enumerable.Repeat("", table.Fields.Count()).ToArray();
var emptyFilters = new List <QvxField>();
foreach (var whereCondition in where)
{
int m = Array.FindIndex(table.Fields, element => element.FieldName == whereCondition.Field);
if (m >= 0)
{
if (m > (ADim - 1))
{
// Only dimensions can be filtered
throw new QvxPleaseSendReplyException(QvxResult.QVX_UNSUPPORTED_COMMAND, String.Format("Field \"{0}\" is not a dimension and can't be filtered", whereCondition.Field));
}
else if ("".Equals(whereCondition.Value))
{
// GAMS API doesn't allow empty filters, so we have to filter them ourselves
emptyFilters.Add(table.Fields[m]);
}
else
{
strFilter[m] = whereCondition.Value;
}
}
else
{
throw new QvxPleaseSendReplyException(QvxResult.QVX_FIELD_NOT_FOUND, String.Format("The field \"{0}\" is not valid", whereCondition.Field));
}
}
using (BlockingCollection <QvxDataRow> buffer = new BlockingCollection <QvxDataRow>())
{
// Start reading thread
Exception exception = null;
var readTask = Task.Run(() =>
{
try
{
gdx.gdxDataReadRawFastFilt(SymNr, strFilter, FilterProc);
}
catch (Exception e)
{
exception = e;
}
finally
{
// Signal the end of the data
buffer.CompleteAdding();
}
});
int FilterProc(IntPtr IndxPtr, IntPtr ValsPtr, IntPtr Uptr)
{
double[] managedArrayVals = new double[gamsglobals.val_max];
Marshal.Copy(ValsPtr, managedArrayVals, 0, gamsglobals.val_max);
int[] managedArrayIndx = new int[gamsglobals.maxdim];
Marshal.Copy(IndxPtr, managedArrayIndx, 0, gamsglobals.maxdim);
QvxDataRow row = mapRow(managedArrayIndx, managedArrayVals, emptyFilters);
if (row != null)
{
buffer.Add(row);
}
return(1);
}
// Writing process
foreach (QvxDataRow row in buffer.GetConsumingEnumerable())
{
yield return(row);
}
if (exception != null)
{
throw exception;
}
}
}
QvxDataRow mapRow(int[] Keys, double[] Vals, List <QvxField> emptyFilters = null)
{
i = 0;
var row = new QvxDataRow();
// Read the dimensions
for (j = 0; j < ADim; j++)
{
if (dimensionCache[j] == null)
{
dimensionCache[j] = new Dictionary <int, string>();
}
UelName = null;
if (dimensionCache[j].ContainsKey(Keys[j]))
{
UelName = dimensionCache[j][Keys[j]];
}
else
{
gdx.gdxUMUelGet(Keys[j], ref UelName, ref IDum);
dimensionCache[j][Keys[j]] = UelName;
}
if (UelName != null)
{
QvxField field = table.Fields[i++];
if (selectedFields.Contains(field.FieldName))
{
row[field] = UelName;
}
// we check the empty filters, as GAMS API doesn't do it
if (emptyFilters != null && emptyFilters.Contains(field) && !string.IsNullOrEmpty(UelName))
{
return(null);
}
}
}
switch (SymTyp)
{
// SET
case gamsglobals.dt_set:
if (gdx.gdxGetElemText((int)Vals[GMS_VAL_LEVEL], ref msg, ref IDum) != 0)
{
QvxField field2 = table.Fields[i++];
if (selectedFields.Contains(field2.FieldName))
{
row[field2] = msg;
}
}
else
{
QvxField field2 = table.Fields[i++];
if (selectedFields.Contains(field2.FieldName))
{
row[field2] = Y_STRING;
}
}
break;
// PARAMETER
case gamsglobals.dt_par:
// Value
readValueField(row, table.Fields[i++], table.Fields[i++], Vals[GMS_VAL_LEVEL]);
if (!string.IsNullOrEmpty(sText) && ADim == 0)
{
QvxField field = table.Fields[i++];
if (selectedFields.Contains(field.FieldName))
{
row[field] = sText;
}
}
break;
// EQUATION and VARIABLE
case gamsglobals.dt_equ:
case gamsglobals.dt_var:
int[] gms_values = { GMS_VAL_LEVEL, GMS_VAL_MARGINAL, GMS_VAL_LOWER, GMS_VAL_UPPER, GMS_VAL_SCALE };
foreach (int gms_value in gms_values)
{
// Value
readValueField(row, table.Fields[i++], table.Fields[i++], Vals[gms_value]);
}
break;
}
return(row);
}
/// <summary>This method reads a value separated in two fields, the first with the numeric value and the second with the special value description.</summary>
void readValueField(QvxDataRow pRow, QvxField numberField, QvxField specialField, double pVal)
{
Boolean isSpecialValue = false;
// Value
if (selectedFields.Contains(numberField.FieldName))
{
pRow[numberField] = val2str(pVal, msg, out isSpecialValue, true, false);
}
// Value (Special)
if (selectedFields.Contains(specialField.FieldName))
{
pRow[specialField] = val2str(pVal, msg, out isSpecialValue, false, true);
}
else if (isSpecialValue)
{
// If the value is special, but the "Special value" column is not selected, we throw an error
throw new QvxPleaseSendReplyException(QvxResult.QVX_FIELD_NOT_FOUND, String.Format("The field \"{0}\" contains special values, so the field \"{1}\" has to be selected", numberField.FieldName, specialField.FieldName));
}
}
/// <summary>This method generates the final value of a field, that can be a normal number, an acronym, infinite, ...</summary>
/// <param name="returnNumber">If true, the value of a number will be returned as a double</param>
/// <param name="returnSpecial">If true, the value of a special value (infinite, epsilon, acronym, ...) will be returned as a string</param>
dynamic val2str(double val, string s, out Boolean isSpecial, Boolean returnNumber = true, Boolean returnSpecial = true)
{
string[] gmsSVText = { "UNdef", "NA", "+Inf", "-Inf", "Eps", "0", "AcroN" };
int sv = 0;
if (gdx.gdxAcronymName(val, ref s) != 0)
{
isSpecial = true;
return(returnSpecial ? s : null);
}
else
{
gdx.gdxMapValue(val, ref sv);
if (gamsglobals.sv_normal != sv)
{
isSpecial = true;
return(returnSpecial ? gmsSVText[sv] : null);
}
else
{
isSpecial = false;
if (returnNumber)
{
return(val);
}
else
{
return(null);
}
}
}
}
}
}
