FEAT: topk function in all backends. #2061
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
9prady9
previously requested changes
Feb 22, 2018
docs/details/statistics.dox
Outdated
| @@ -1,7 +1,7 @@ | |||
| /*! | |||
| \page batch_detail_stat statistics | |||
|
|
|||
| This function performs the operation across all batches present in the input simultaneously. | |||
| This function performs the operation across all dimension of the input array. | |||
src/api/c/topk.cpp
Outdated
| using namespace detail; | ||
|
|
||
| template<typename T> | ||
| af_err topkWithIndices(af_array *v, af_array* i, const af_array in, |
There was a problem hiding this comment.
can you change this function name to be topk as well since we are not explicitly saying with indices anywhere now.
| array. The indices along with their values are returned. If the input is a | ||
| multi-dimensional array, the indices will be the index of the value in that | ||
| dimension. Order of duplicate values are not preserved. This function is | ||
| optimized for small values of k. |
There was a problem hiding this comment.
It would be nice if we can add some sort of guideline as to from which value of k does the performance deteriorate.
There was a problem hiding this comment.
This would be different for different devices and implementations.
test/topk.cpp
Outdated
| TYPED_TEST_CASE(TopK, TestTypes); | ||
|
|
||
| template<typename T> | ||
| void topkIndexTest(const unsigned ndims, const dim_t* dims, |
There was a problem hiding this comment.
We can just make it topkTest instead of topkIndexTest now.
|
@umar456 why not partial_sort for cpu devices? |
umar456
force-pushed
the
topk
branch
2 times, most recently
from
68e8449
to
9a8fd9b
Compare
umar456
commented
Feb 24, 2018
| array. The indices along with their values are returned. If the input is a | ||
| multi-dimensional array, the indices will be the index of the value in that | ||
| dimension. Order of duplicate values are not preserved. This function is | ||
| optimized for small values of k. |
There was a problem hiding this comment.
This would be different for different devices and implementations.
CUDA backend alone implements a custom kernel to fetch top k elements without sorting all the values. CPU backends sorts the data and fetch the top k elements. The OpenCL backend is optimized for CPU devices to map the memory and perform a partial sort to get the results.
9prady9
approved these changes
Feb 25, 2018
Closed
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
CUDA backend alone implements a custom kernel to fetch top k elements
without sorting all the values. CPU backends sorts the data and fetch
the top k elements. The OpenCL backend is optimized for CPU devices
to map the memory and perform a partial sort to get the results.
Sponsored by SDL