/// <summary>
/// Finds the offset for a single item assignment to the array.
/// </summary>
/// <param name="arr">The array we are assigning to.</param>
/// <returns>The offset or -1 if this is not a single assignment.</returns>
internal npy_intp SingleAssignOffset(ndarray arr)
{
// Check to see that there are just newaxis, ellipsis, intp or bool indexes
for (int i = 0; i < num_indexes; i++)
{
switch (IndexType(i))
{
case NpyIndexType.NPY_INDEX_NEWAXIS:
case NpyIndexType.NPY_INDEX_ELLIPSIS:
case NpyIndexType.NPY_INDEX_INTP:
case NpyIndexType.NPY_INDEX_BOOL:
break;
default:
return(-1);
}
}
// Bind to the array and calculate the offset.
NpyIndexes bound = Bind(arr);
{
npy_intp offset = 0;
int nd = 0;
for (int i = 0; i < bound.num_indexes; i++)
{
switch (bound.IndexType(i))
{
case NpyIndexType.NPY_INDEX_NEWAXIS:
break;
case NpyIndexType.NPY_INDEX_INTP:
offset += arr.Stride(nd++) * bound.GetIntP(i);
break;
case NpyIndexType.NPY_INDEX_SLICE:
// An ellipsis became a slice on binding.
// This is not a single item assignment.
return(-1);
default:
// This should never happen
return(-1);
}
}
if (nd != arr.ndim)
{
// Not enough indexes. This is not a single item.
return(-1);
}
return(offset);
}
}
public Object this[params object[] args]
{
get
{
ndarray result;
NpyIndexes indexes = new NpyIndexes();
{
NpyUtil_IndexProcessing.IndexConverter(this.arr.ravel(), args, indexes);
result = NpyCoreApi.IterSubscript(this, indexes);
}
if (result.ndim == 0)
{
return(result.GetItem(0));
}
else
{
return(result);
}
}
set
{
NpyIndexes indexes = new NpyIndexes();
{
NpyUtil_IndexProcessing.IndexConverter(this.arr.ravel(), args, indexes);
if (indexes.NumIndexes == 1)
{
// Special cases for single assigment.
switch (indexes.IndexType(0))
{
case NpyIndexType.NPY_INDEX_INTP:
SingleAssign(indexes.GetIntP(0), value);
return;
case NpyIndexType.NPY_INDEX_BOOL:
if (indexes.GetBool(0))
{
SingleAssign(0, value);
}
return;
default:
break;
}
}
ndarray array_val = np.FromAny(value, arr.Dtype, 0, 0, 0, null);
NpyCoreApi.IterSubscriptAssign(this, indexes, array_val);
}
}
}