[Fix] Fix index error when using multi-samplers strategy

[zhangtingyu11]

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Motivation

fix index error when using multi-samplers strategy

Modification

Just change index from last_fps_end_index:fps_sample_range to last_fps_end_index:fps_sample_range +last_fps_end_index based on the issue #2082

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[HAOCHENYE]

Thanks for your contribution~~.
I think fps_sample_range_list should be a list of indexes represented for the target range of sampled points.
For example, when fps_sample_range_list=-1 (default value), it means it will sample the points from the first(index: 0) to the last(index: -1):
Besides, fps_sample_range_list has the key word: range, just like Python built-in range, it should accept the arguments which mean the first index and the last index.

But this pr seems to assume fps_sample_range_list is a list, and each element means the number of sampled. I think it is not consistent with its default value and argument name.

What do you think of it?

[zhangtingyu11]

Thanks for your contribution~~. I think fps_sample_range_list should be a list of indexes represented for the target range of sampled points. For example, when fps_sample_range_list=-1 (default value), it means it will sample the points from the first(index: 0) to the last(index: -1): Besides, fps_sample_range_list has the key word: range, just like Python built-in range, it should accept the arguments which mean the first index and the last index.

But this pr seems to assume fps_sample_range_list is a list, and each element means the number of sampled. I think it is not consistent with its default value and argument name.

What do you think of it?

You are right.I have changed index when updating last_fps_end_index.For example, if there are 3000 points,and the fps_sample_list is [1000,2000,3000].The last_fps_end_index will be 0,1000,2000 in each loop,and the points should be choosen with index in (0~1000),(1000~2000),(2000~3000).I think this matches your idea.

[HAOCHENYE]

LGTM.

[yaqi0510]

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