<p dir="auto">Currently gradients can only be computed manually in C++ or automatically in Python with tf.gradients. Work on registering C++ implemented gradients for all the OPs has started. However, there is currently no easy way to automatically use those gradients to generate a graph. The C-api also does not have gradient creation calls yet.</p>
<p dir="auto">This supercedes the gradient part of <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="121630790" data-permission-text="Title is private" data-url="https://github.com/tensorflow/tensorflow/issues/476" data-hovercard-type="issue" data-hovercard-url="/tensorflow/tensorflow/issues/476/hovercard" href="https://github.com/tensorflow/tensorflow/issues/476">#476</a>, since the rest of <a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="121630790" data-permission-text="Title is private" data-url="https://github.com/tensorflow/tensorflow/issues/476" data-hovercard-type="issue" data-hovercard-url="/tensorflow/tensorflow/issues/476/hovercard" href="https://github.com/tensorflow/tensorflow/issues/476">#476</a>'s issue was addressed.</p>
<p dir="auto">I have started <a href="https://github.com/kmalakoff/tensorflow-node">porting Tensorflow to Node.js</a> and was wondering about the status of gradients support in the C and C++ APIs:</p>
<ul dir="auto">
<li><a href="https://www.tensorflow.org/versions/r0.12/how_tos/language_bindings/index.html" rel="nofollow">https://www.tensorflow.org/versions/r0.12/how_tos/language_bindings/index.html</a></li>
<li><a href="https://github.com/tensorflow/tensorflow/blob/master/tensorflow/g3doc/resources/roadmap.md">https://github.com/tensorflow/tensorflow/blob/master/tensorflow/g3doc/resources/roadmap.md</a></li>
</ul>
<p dir="auto">Could I ask for some help and / or offer some assistance? A couple of ideas:</p>
<ol dir="auto">
<li>I would be happy to test the work-in-progress API in Node.js using either of both <a href="https://github.com/kmalakoff/tensorflow-node/tree/master/src/native/c">C</a> or <a href="https://github.com/kmalakoff/tensorflow-node/tree/master/src/native/cc">C++</a>. I have tried both APIs and would be happy to maintain both as a test case.</li>
<li>I would be happy to receive some guidance from someone on the tensorflow team on how to implement gradients / training without an official API. I see from this issue (<a class="issue-link js-issue-link" data-error-text="Failed to load title" data-id="177892952" data-permission-text="Title is private" data-url="https://github.com/tensorflow/tensorflow/issues/4473" data-hovercard-type="issue" data-hovercard-url="/tensorflow/tensorflow/issues/4473/hovercard" href="https://github.com/tensorflow/tensorflow/issues/4473">#4473</a>) that it might be possible, but it has been hard to study the Python and OCAML code to understand what to do. Some pseudocode or links to existing code that would need to replicated could be enough.</li>
<li>Something else? For example, I could help move the gradient API forward by working with someone on the tensorflow team.</li>
</ol>
<p dir="auto">Let me know if you have any suggestions for a path forward. Thank you!</p>