public ValueEval Evaluate(ValueEval[] args, int srcCellRow, int srcCellCol)
{
ValueEval arg3 = null;
switch (args.Length)
{
case 4:
arg3 = args[3]; // important: assumed array element Is never null
break;
case 3:
break;
default:
// wrong number of arguments
return(ErrorEval.VALUE_INVALID);
}
try
{
// Evaluation order:
// arg0 lookup_value, arg1 table_array, arg3 range_lookup, Find lookup value, arg2 row_index, fetch result
ValueEval lookupValue = OperandResolver.GetSingleValue(args[0], srcCellRow, srcCellCol);
AreaEval tableArray = LookupUtils.ResolveTableArrayArg(args[1]);
bool IsRangeLookup = LookupUtils.ResolveRangeLookupArg(arg3, srcCellRow, srcCellCol);
int colIndex = LookupUtils.LookupIndexOfValue(lookupValue, LookupUtils.CreateRowVector(tableArray, 0), IsRangeLookup);
int rowIndex = LookupUtils.ResolveRowOrColIndexArg(args[2], srcCellRow, srcCellCol);
ValueVector resultCol = CreateResultColumnVector(tableArray, rowIndex);
return(resultCol.GetItem(colIndex));
}
catch (EvaluationException e)
{
return(e.GetErrorEval());
}
}
/**
* Returns one column from an <tt>AreaEval</tt>
*
* @(#VALUE!) if colIndex Is negative, (#REF!) if colIndex Is too high
*/
private ValueVector CreateResultColumnVector(AreaEval tableArray, int rowIndex)
{
if (rowIndex >= tableArray.Height)
{
throw EvaluationException.InvalidRef();
}
return(LookupUtils.CreateRowVector(tableArray, rowIndex));
}
/**
* Returns one column from an <tt>AreaEval</tt>
*
* @(#VALUE!) if colIndex Is negative, (#REF!) if colIndex Is too high
*/
private ValueVector CreateResultColumnVector(AreaEval tableArray, int colIndex)
{
if (colIndex >= tableArray.Width)
{
throw EvaluationException.InvalidRef();
}
return(LookupUtils.CreateColumnVector(tableArray, colIndex));
}
private static ValueVector CreateVector(AreaEval ae)
{
ValueVector result = LookupUtils.CreateVector(ae);
if (result != null)
{
return(result);
}
// extra complexity required to emulate the way LOOKUP can handles these abnormal cases.
throw new InvalidOperationException("non-vector lookup or result areas not supported yet");
}
private static LookupValueComparer CreateLookupComparer(ValueEval lookupValue, bool matchExact)
{
if (matchExact && lookupValue is StringEval)
{
String stringValue = ((StringEval)lookupValue).StringValue;
if (IsLookupValueWild(stringValue))
{
throw new Exception("Wildcard lookup values '" + stringValue + "' not supported yet");
}
}
return(LookupUtils.CreateLookupComparer(lookupValue));
}
public override ValueEval Evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1,
ValueEval arg2, ValueEval arg3)
{
try
{
// Evaluation order:
// arg0 lookup_value, arg1 table_array, arg3 range_lookup, find lookup value, arg2 col_index, fetch result
ValueEval lookupValue = OperandResolver.GetSingleValue(arg0, srcRowIndex, srcColumnIndex);
AreaEval tableArray = LookupUtils.ResolveTableArrayArg(arg1);
bool isRangeLookup = LookupUtils.ResolveRangeLookupArg(arg3, srcRowIndex, srcColumnIndex);
int rowIndex = LookupUtils.LookupIndexOfValue(lookupValue, LookupUtils.CreateColumnVector(tableArray, 0), isRangeLookup);
int colIndex = LookupUtils.ResolveRowOrColIndexArg(arg2, srcRowIndex, srcColumnIndex);
ValueVector resultCol = CreateResultColumnVector(tableArray, colIndex);
return(resultCol.GetItem(rowIndex));
}
catch (EvaluationException e)
{
return(e.GetErrorEval());
}
}
public ValueEval Evaluate(ValueEval[] args, int srcCellRow, int srcCellCol)
{
switch (args.Length)
{
case 3:
break;
case 2:
// complex rules to choose lookupVector and resultVector from the single area ref
throw new Exception("Two arg version of LOOKUP not supported yet");
default:
return(ErrorEval.VALUE_INVALID);
}
try
{
ValueEval lookupValue = OperandResolver.GetSingleValue(args[0], srcCellRow, srcCellCol);
AreaEval aeLookupVector = LookupUtils.ResolveTableArrayArg(args[1]);
AreaEval aeResultVector = LookupUtils.ResolveTableArrayArg(args[2]);
ValueVector lookupVector = CreateVector(aeLookupVector);
ValueVector resultVector = CreateVector(aeResultVector);
if (lookupVector.Size > resultVector.Size)
{
// Excel seems to handle this by accessing past the end of the result vector.
throw new Exception("Lookup vector and result vector of differing sizes not supported yet");
}
int index = LookupUtils.LookupIndexOfValue(lookupValue, lookupVector, true);
return(resultVector.GetItem(index));
}
catch (EvaluationException e)
{
return(e.GetErrorEval());
}
}
private static ValueVector EvaluateLookupRange(ValueEval eval)
{
if (eval is RefEval)
{
RefEval re = (RefEval)eval;
return(new SingleValueVector(re.InnerValueEval));
}
if (eval is AreaEval)
{
ValueVector result = LookupUtils.CreateVector((AreaEval)eval);
if (result == null)
{
throw new EvaluationException(ErrorEval.NA);
}
return(result);
}
// Error handling for lookup_range arg Is also Unusual
if (eval is NumericValueEval)
{
throw new EvaluationException(ErrorEval.NA);
}
if (eval is StringEval)
{
StringEval se = (StringEval)eval;
double d = OperandResolver.ParseDouble(se.StringValue);
if (double.IsNaN(d))
{
// plain string
throw new EvaluationException(ErrorEval.VALUE_INVALID);
}
// else looks like a number
throw new EvaluationException(ErrorEval.NA);
}
throw new Exception("Unexpected eval type (" + eval.GetType().Name + ")");
}