get_group_rank_from_world_rank

Description

Obtains the group rank ID of the process in the group using the world rank ID.

Prototype

def get_group_rank_from_world_rank(world_rank_id, group)

Parameters

Parameter	Input/Output	Description
world_rank_id	Input	An int. Rank ID of the process in hccl_world_group.
group	Input	A string containing a maximum of 128 bytes, including the end character. Group name, which can be a user-defined value or hccl_world_group.

Parameter

Input/Output

Description

world_rank_id

Input

An int.

Rank ID of the process in hccl_world_group.

group

Input

A string containing a maximum of 128 bytes, including the end character.

Group name, which can be a user-defined value or hccl_world_group.

Returns

An int for the rank ID of a process in a group

Constraints

This API must be called after the initialization of collective communication is complete.
The caller rank must be within the range defined by the group argument passed to this API call. Otherwise, the API call fails.
After the create_group call, call this API to convert the world rank ID to the group rank ID.

Applicability

Atlas Training Series Product

Example

The following is only a code snippet and cannot be executed. For details about how to call the HCCL Python APIs to perform collective communication, see Sample Code.

from npu_bridge.npu_init import *
create_group("myGroup", 4, [0, 1, 2, 3])
groupRankId = get_group_rank_from_world_rank(8, "myGroup")

Parent topic: hccl.manage.api