From commits-return-93651-archive-asf-public=cust-asf.ponee.io@mxnet.incubator.apache.org Fri Jul 19 00:55:57 2019 Return-Path: X-Original-To: archive-asf-public@cust-asf.ponee.io Delivered-To: archive-asf-public@cust-asf.ponee.io Received: from mail.apache.org (hermes.apache.org [207.244.88.153]) by mx-eu-01.ponee.io (Postfix) with SMTP id CB54D180686 for ; Fri, 19 Jul 2019 02:55:56 +0200 (CEST) Received: (qmail 14951 invoked by uid 500); 19 Jul 2019 00:55:56 -0000 Mailing-List: contact commits-help@mxnet.incubator.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@mxnet.incubator.apache.org Delivered-To: mailing list commits@mxnet.incubator.apache.org Received: (qmail 14874 invoked by uid 99); 19 Jul 2019 00:55:56 -0000 Received: from ec2-52-202-80-70.compute-1.amazonaws.com (HELO gitbox.apache.org) (52.202.80.70) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 19 Jul 2019 00:55:56 +0000 From: GitBox To: commits@mxnet.apache.org Subject: [GitHub] [incubator-mxnet] IvyBazan commented on a change in pull request #15517: Tensor Inspector Tutorial Message-ID: <156349775553.23858.15265012180261937695.gitbox@gitbox.apache.org> Date: Fri, 19 Jul 2019 00:55:55 -0000 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit IvyBazan commented on a change in pull request #15517: Tensor Inspector Tutorial URL: https://github.com/apache/incubator-mxnet/pull/15517#discussion_r305163728 ########## File path: docs/faq/tensor_inspector_tutorial.md ########## @@ -0,0 +1,168 @@ + + + + + + + + + + + + + + + +# Use TensorInspector to Help Debug Operators + +## Introduction + +When developing new operators, developers need to deal with tensor objects extensively. This new utility, Tensor Inspector, mainly aims to help developers debug by providing unified interfaces to print, check, and dump the tensor value. To developers' convenience, this utility works for all the three data types: Tensors, TBlobs, and NDArrays. Also, it supports both CPU and GPU tensors. + + +## Usage + +This utility is located in `src/common/tensor_inspector.h`. To use it in any operator code, just include `tensor_inspector`, construct an `TensorInspector` object, and call the APIs on that object. You can run any script that uses the operator you just modified then. + +The screenshot below shows a sample usage in `src/operator/nn/convolution-inl.h`. + +![Screen Shot 2019-07-08 at 5 03 46 PM](https://user-images.githubusercontent.com/16669457/60850062-68690e00-a1a2-11e9-8268-033edde17aa4.png) + + +## Functionalities/APIs + +### Create a TensorInspector Object from Tensor, TBlob, and NDArray Objects + +You can create a `TensorInspector` object by passing in two things: 1) an object of type `Tensor`, `Tbob`, or `NDArray`, and 2) an `RunContext` object. + +Essentially, `TensorInspector` can be understood as a wrapper class around `TBlob`. Internally, the `Tensor`, `Tbob`, or `NDArray` object that you passed in will be converted to a `TBlob` object. The `RunContext` object is used when the the tensor is a GPU tensor; in such a case, we need to use the context information to copy the data from GPU memory to CPU/main memory. + +Below are the three constructors: + +```c++ +// Construct from Tensor object +template +TensorInspector(const mshadow::Tensor& ts, const RunContext& ctx); + +// Construct from TBlob object +TensorInspector(const TBlob& tb, const RunContext& ctx); + +// Construct from NDArray object +TensorInspector(const NDArray& arr, const RunContext& ctx): +``` + +### Print Tensor Value (Static) + +To print out the tensor value in a nicely structured way, you can use this API: + +```c++ +void print_string(); +``` + +This API will print the entire tensor to `std::cout` and preserve the shape (it supports all dimensions from 1 and up). You can copy the output and interpret it with any `JSON` loader. Also, on the last line of the output you can find some useful information about the tensor. Refer to the case below, we are able to know that this is a float-typed tensor with shape 20x1x5x5. Review comment: Suggested edit for clarity and flow: "You can find some useful information about the tensor on the last line of the output." ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: users@infra.apache.org With regards, Apache Git Services