[ 
https://issues.apache.org/jira/browse/SYSTEMML-1736?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
 ]

Mike Dusenberry reassigned SYSTEMML-1736:
-----------------------------------------

    Assignee: Mike Dusenberry  (was: Fei Hu)

> Add new 2D top_k utility function
> ---------------------------------
>
>                 Key: SYSTEMML-1736
>                 URL: https://issues.apache.org/jira/browse/SYSTEMML-1736
>             Project: SystemML
>          Issue Type: Sub-task
>            Reporter: Mike Dusenberry
>            Assignee: Mike Dusenberry
>
> We should add a new {{top_k2d}} utility function (in {{nn/util.dml}}) that 
> accepts a matrix {{X}} and return matrices {{values}} and {{indices}} with 
> the top {{k}} values (i.e. probabilities) and associated indices (i.e. 
> classes) along a certain dimension.  This will be modeled after the 
> [{{top_k}} function in TensorFlow | 
> https://www.tensorflow.org/api_docs/python/tf/nn/top_k].  For the 2D case, 
> {{top_k}} will operate on the channels dimension.  A typical use case here is 
> that in which {{X}} is the output of a {{softmax2d}} layer (so each channel 
> contains a set of normalized class probabilities), and {{values}} and 
> {{indices}} will contain the top {{k}} probabilities and indices along the 
> channel axis.  This scenario would be common in an image segmentation 
> problem, in which every pixel of the output image will have a set of class 
> probabilities along the channel axis.
> Having these {{top-k}} functions will allow us to extract either predict a 
> single class for each item, or the top {{k}} classes, and therefore may be 
> more useful that a {{predict_class}} function.
> Although we will use {{values}} and {{indices}} as the names of the returned 
> matrices within the functions, in practice, one is likely to name the results 
> {{probs}} and {{classes}} in the calling environment.



--
This message was sent by Atlassian JIRA
(v6.4.14#64029)

Reply via email to