ILNumerics Ultimate VS

SizeGetSeqIndex Method (UInt32, UInt32)

ILNumerics Ultimate VS Documentation
ILNumerics - Technical Application Development
Retrieves the sequential index into an array stored according to this size descriptor object based on the provided indices d0 and d1.

[ILNumerics Core Module]

Namespace:  ILNumerics
Assembly:  ILNumerics.Core (in ILNumerics.Core.dll) Version: (5.5.7503.3146)

public uint GetSeqIndex(
	uint d0,
	uint d1


Type: SystemUInt32
Index into the first dimension.
Type: SystemUInt32
Index into the second dimension.

Return Value

Type: UInt32
Storage element index addressing the element in memory.

IndexOutOfRangeException if the leading dimension specifier d0 is equal to or greater than the length of the first dimension.
IndexOutOfRangeException if d1 is equal or greater than the length of the second dimension and the resulting index points to a non-existing element.

For arrays of matrix shape d0 references the index of the row and d1 references the index of the column of the sequential index to return.

More general, for n-dimensional arrays the first index corresponds to the position in the first (index: 0) dimension and the second index to the position of the element in the second dimension (index: 1).

If the array refered to by this size stores more dimensions than addressed by this function the last index parameter d1 can exceed the limits of its corresponding dimension. In this case the sequential index to be returned is computed by subsequently merging trailing dimensions and applying the superflous modulos of the value of d1 to the next dimension, correspondingly. This process is repeated until either the number of dimensions is reached or the modified new value of d1 reaches 0.

This function recognizes arbitrary strides. It expects all sizes (dimension lengths, strides, the base offset and the number of elements) to fit into MaxValue. Use one of the overloads with Int64 parameters if you are dealing with very big arrays or negative indices.

Performance hint: this function (and all corresponding overloads) are optimized for the case where the number of index parameters provided corresponds to the number of dimensions in the array and all provided index parameters are within the range of their corresponding dimension. The functions, however, handle arbitrary cases, including addressing, merging and ommitting trailing dimensions. Any of those extended features may introduce a performance penalty, though.

[ILNumerics Core Module]

See Also