integer_sequence

Applicability

Product	Supported
Atlas A3 training products/Atlas A3 inference products	√
Atlas A2 training products/Atlas A2 inference products	√
Atlas 200I/500 A2 inference products	x
Atlas inference product's AI Core	√
Atlas inference product's Vector Core	x
Atlas training products	x

Function

index_sequence is a class template provided by Ascend C. It is used to generate an integer sequence for building and is applicable to template metaprogramming.

make_index_sequence is a template provided by Ascend C. Generally, make_index_sequence is used to create an object of the index_sequence type to generate an integer sequence from 0 to N-1.

Prototype

template<size_t... Idx>
using index_sequence = IntegerSequence<size_t, Idx...>;

template<size_t N>
using make_index_sequence = MakeIntegerSequence<size_t, N>;

Parameters

**Table 1** Template parameters
Parameter	Description
...Idx	Formal parameter package of a sequence. size_t (long unsigned int for 64-bit systems and unsigned int for non-64-bit systems)
N	Size of the generated integer sequence. size_t (long unsigned int for 64-bit systems and unsigned int for non-64-bit systems)

Restrictions

N ranges from 0 to 64.
index_sequence is a sequence with the maximum length of 64.

Returns

None

Example

Generate and print an integer sequence of length 5.

template<size_t... Is> 
__aicore__  inline void PrintIndexSequence(AscendC::Std::index_sequence<Is...>) {
   ((AscendC::printf(" Is:%lu", Is)), ...);
}
__aicore__ inline void Process()
{
    PrintIndexSequence(AscendC::Std::make_index_sequence<5>{}); // The print result is 0, 1, 2, 3, or 4.
    PrintIndexSequence(AscendC::Std::index_sequence<0,1,2,10,8000>{}); // The print result is 0, 1, 2, 10, or 8000.
}

Parent topic: Common Tools