private object EvaluteMultiIndexingExpression(MultiIndexingExpression e, VariableContext context)
{
object value = Evaluate(e.Operand, context);
int[] indexers = e.Indexers.Select(i => Types.ConvertValue <int>(Evaluate(i, context))).ToArray();
if (e.Operand.Type.IsArray)
{
Array array = value as Array;
return(array.GetValue(indexers[0]));
}
else if (e.Operand.Type.Equals(typeof(Matrix)))
{
Matrix m = value as Matrix;
if (indexers.Length == 1)
{
return(m.GetRow(indexers[0] - 1));
}
else
{
return(m[indexers[0] - 1, indexers[1] - 1]);
}
}
else
{
Vector v = value as Vector;
return(v[indexers[0] - 1]);
}
}
protected override Expression CompileIndexingExpression(Expression operand, int lambdaLevel)
{
PushPosition();
Move();
List <Expression> indexers = new List <Expression>();
while (true)
{
indexers.Add(Compile(lambdaLevel));
if (IsPunctuationOf(","))
{
Move();
}
else
{
SkipPunctuation("]");
break;
}
}
Expression result = new MultiIndexingExpression(operand, indexers.ToArray(), PeekPos(), Pos);
PopPosition();
return(result);
}
private void CheckMultiIndexingExpression(MultiIndexingExpression e, TypeCheckingContext context)
{
PerformTypeChecking(e.Operand, context);
foreach (Expression indexer in e.Indexers)
{
PerformTypeChecking(indexer, context);
}
if (!e.Indexers.All(i => Types.IsNumberType(i.Type)))
{
context.ErrorProvider.ThrowException("Matrix multi indexer parameters must be of number types.", e);
}
if (e.Operand.Type.IsArray)
{
if (e.Indexers.Length != 1)
{
context.ErrorProvider.ThrowException("Array multi indexer must be of 1 parameter.", e);
}
else
{
e.Type = e.Operand.Type.GetElementType();
}
}
else if (e.Operand.Type == typeof(Matrix))
{
if (e.Indexers.Length == 1)
{
e.Type = typeof(double[]);
}
else if (e.Indexers.Length == 2)
{
e.Type = typeof(double);
}
else
{
context.ErrorProvider.ThrowException("Matrix multi indexer must be of 1 or 2 parameters.", e);
}
}
else if (e.Operand.Type == typeof(Vector))
{
if (e.Indexers.Length == 1)
{
e.Type = typeof(double);
}
else
{
context.ErrorProvider.ThrowException("Vector multi indexer must be of 1 parameter.", e);
}
}
else
{
context.ErrorProvider.ThrowException("Only matrix can use multi indexer.", e);
}
}
