IMO, its unnecessary. this is only my opinion and you are free to disagree. With more opinions one or some of us will have to commit to the majority of the opinion.
On Sat, Sep 29, 2018 at 10:35 PM YiZhi Liu <[email protected]> wrote: > No you haven't answered my question "Since you agree to have 30+ > operators have Builder, what prevents from > having all of them have Builder?" > On Sat, Sep 29, 2018 at 7:30 PM Naveen Swamy <[email protected]> wrote: > > > > I think we have had enough of an debate between the two of us and I have > > already listed my reasons, I will stop here and see what others say > given > > my reasoning. > > > > -1 to #2) > > > > Also, by lecture I meant to say "I don't want to list all the problems > > with unnecessary complications and talk about how to design software" > > > > On Sat, Sep 29, 2018 at 10:15 PM YiZhi Liu <[email protected]> wrote: > > > > > And if we find incorrect declaration, we fix it, not simply assuming > > > many of them also has problem and we cannot rely on them - otherwise > > > the type-safe APIs in Scala also does not make sense. > > > On Sat, Sep 29, 2018 at 7:10 PM YiZhi Liu <[email protected]> wrote: > > > > > > > > It also makes sense to me if we have it under namespace NDArray, not > > > > creating new JavaNDArray. But again, uniform experience is important. > > > > > > > > What I responded is your comment "keep scala macros minimum", I don't > > > > think "scala macro" equals "cryptic code". Even though it does, what > > > > we need to do is to find an alternative way to do code generation, > not > > > > making code generation minimum. > > > > > > > > Since you agree to have 30+ operators have Builder, what prevents > from > > > > having all of them have Builder? > > > > - They're auto-generated, the auto-generation "cryptic" code is > anyway > > > > there. And "two different paths of code" (though I don't totally > > > > agree) is anyway there. > > > > - What else? 200+ classes is a very tiny increasing in file size > > > > (~3MB) compare to current status. And won't have any performance > issue > > > > on modern JVM. > > > > > > > > Just remind, technical discussion is not about who gives who a > lecture. > > > > On Sat, Sep 29, 2018 at 6:41 PM Naveen Swamy <[email protected]> > wrote: > > > > > > > > > > Well, I am not sure(I don't think) we need Builder for every API in > > > > > NDArray. For APIs that take long list of parameters, I agree to add > > > Builder. > > > > > Look at the API distribution based on number of arguments here: > > > > > https://gist.github.com/nswamy/2dea72e514cc7bfc675f68aef9fe78bb > > > > > about 30 APIs have 7 or more arguments.. I agree to add Builders > for > > > these > > > > > APIs not separately but to the existing Scala APIs but not > separately > > > only > > > > > for Java. > > > > > APIs sorted by number of arguments is here, take a look : > > > > > https://gist.github.com/nswamy/e941cb94658b3960eec40bf00b970ac5 > > > > > > > > > > Many of the arguments i think are actually mandatory but > incorrectly > > > > > declared optional on the backend, for example look at SwapAxis > > > > > "def SwapAxis (data : NDArray, dim1 : Option[Int] = None, dim2 : > > > > > Option[Int] = None, out : Option[NDArray] = None) : > NDArrayFuncReturn" > > > > > Why is dim1 and dim2 Optional, this is an error in the declaration > on > > > the > > > > > backend, I think there might be many of these? > > > > > > > > > > My answers to your other responses are below inline: > > > > > > > > > > On Sat, Sep 29, 2018 at 3:37 PM YiZhi Liu <[email protected]> > wrote: > > > > > > > > > > > Some of my comments inline: > > > > > > > > > > > > > Why can we not create the builder just for these APIs( which we > > > > > > discussed), why is it necessary to add 200 Apis > > > > > > It is about unified user-experience. And we get rid of annoying > extra > > > > > > "out=null" in every operator. > > > > > > > > > > > > > Are you suggesting to create builder for each and every API? > > > > > > Only for those are necessary. For NDArray.XXX, yes. > > > > > > > > > > > I think this is a ridiculous list of Builders, I think we can keep > the > > > > > 'out' parameter > > > > > > > > > > > 1) The NDArray APIs in question are not following functional > style of > > > > > > programming, in fact they are just static methods defined on an > > > > > > NDArray object - so Scala users are not losing much by using > null in > > > > > > place of None. > > > > > > You can create a implicit to maintain backward compatibility > > > > > > - I doubt implicit can work in such case from None -> null. > > > > > > > > > > > > > > > > It is just writing getOrElse in your implicit, so it will work. > > > > > scala> implicit def optionStringToString(a: Option[String]): > String = { > > > > > | a.getOrElse(null) > > > > > | } > > > > > > > > > > 2) It is adding 220+ APIs(I understand it is generated) for NDArray > > > alone > > > > > > - As I explained how it can improve user experiences > > > > > > > > > > > I don't think we need to write builders for 221 APIs we have, may > be > > > for 30 > > > > > or so. Uniform experience is good goal but it also has to be > practical > > > and > > > > > make sense. > > > > > > > > > > 3) this is adding another 100s of APIs unnecessarily, we are > starting > > > with > > > > > > NDArray but we can't stop there, we will have to do this for > Symbol, > > > > > > Executor, Iterators, etc., . > > > > > > - This is a good point, actually I prefer not to make > JavaExecutor, > > > > > > JavaIterators > > > > > > > > > > > What I was aiming is also users have the same experience across > > > Interfaces > > > > > - now you are forgoing uniform experience, so like you said its all > > > > > trade-off and a good trade-off doesn't cause too much overhead/ > > > > > > > > > > > > > > > > 4) I don't want to be fixing bugs and maintaining code in 2 > places. > > > > > > - Type-safe parsing is shared. I think Qing is more qualified to > > > comment. > > > > > > > > > > It creates two different paths of code for Scala and Java - how is > it > > > going > > > > > to be shared. I am afraid we are going to make it more complicated > than > > > > > necessary by duplicating code. > > > > > > > > > > > > > > > > > > > > > 5) I want the cryptic code(# scala macros) to a minimum. > > > > > > - MXNet decides to do operator generation in frontend bindings. > It's > > > > > > the developers' responsibility to understand the techniques they > are > > > > > > using. Maybe not a so proper analogy - "I don't know RL / RL is > hard > > > > > > to tune / ..." is not a reason for "I want to keep RL > implementation > > > > > > in MXNet as a small part as possible" > > > > > > > > > > > > Now, this is a response I don't like. I don't know where you were > > > going > > > > > with your analogy but know that it sounds condescending - I am > going to > > > > > ignore(assuming good intentions) that and explain what I mean. > > > > > I here is I the developer/user who deploys MXNet code in > production and > > > > > have to deal with the aftermath myself not you(MXNet developers). > > > > > From your comment it occurs to me you probably have never been on > > > > > pager-duty. I have been on pager-duty both for the code I wrote and > > > those > > > > > that was written by others and thrown over the fence. > > > > > If you get woken up by a beep at the middle of the night, that is > not > > > the > > > > > time to prove your intelligence. Its time to mitigate the issue > asap > > > for > > > > > that your code needs to be easy to follow, should follow well > defined > > > > > patterns, etc., -- i don't need to give you a lecture. > > > > > IMHO It is extremely important for frameworks like Apache MXNet > which > > > are > > > > > used by others for their production to keep code simple and > *cryptic > > > code > > > > > to a minimum* and yes you(we - MXNet developers) are not answering > the > > > > > beepers when your(MXNet) users deploy their code in their > production so > > > > > make their life simple. > > > > > > > > > > 6) increased compilation time & bad developer experience - the > time to > > > > > > compile has gone up quite a bit since we added the APIs last > release > > > on my > > > > > > 3 year old laptop already.. I think adding 400+ APIs > unnecessarily > > > would > > > > > > significantly increase build time and bad developer experience > > > > > > - I don't think increasing such a bit compilation time is a > problem > > > > > > compared to bad user experience. > > > > > > > > > > I am not suggesting bad user experience but to take a practical > > > approach - > > > > > having a bad developer experience is not great either. > > > > > > > > > > > > > > > > > > > > > > 7) I want to keep the core of the framework to be in Scala - > because it > > > > > > allows you to write concise code - Yes it has a bit of learning > > > curve, not > > > > > > everyone needs to know. I would rather invest in solidifying the > > > Scala APIs > > > > > > and add more features in Scala(RNN, Support > > > GluonHybridizedBlock...there is > > > > > > quite bit of work ) - do you want to rewrite everything in Scala > and > > > Java. > > > > > > - I agree with "don't rewrite everything in Scala and Java", IMO > > > > > > JavaNDArray is the only one good to have. JShape, JContext, etc. > are > > > > > > not so necessary. > > > > > > > > > > > > Either you go all Java or make accommodation in Scala code to > work > > > for > > > > > APIs so your users know what to expect(uniform experience across). > > > > > > > > > > > 8) Also, the discussion is not creating NDArray class for Java, > just > > > > > > generate certain APIs to cater for Java incompatibility. > > > > > > - Yes I agree it's about "generate certain APIs to cater for Java > > > > > > incompatibility", though I think NDArray.api.XXX does not meet > Java > > > > > > users' demands. > > > > > > > > > > > On Sat, Sep 29, 2018 at 12:05 PM Naveen Swamy <[email protected]> > > > wrote: > > > > > > > > > > > > > > I know it is about trade-off. I am suggesting a trade-off , > how > > > many > > > > > > apis do we have that takes too many parameters ? > > > > > > > From what I recall its around 20. Why can we not create the > > > builder just > > > > > > for these APIs( which we discussed), why is it necessary to add > 200 > > > Apis ? > > > > > > > Are you suggesting to create builder for each and every API? > > > > > > > > > > > > > > I disagree with your opinion that they are not important and > would > > > like > > > > > > to hear from others. > > > > > > > > > > > > > > I am curious to see how the #2 looks like compared to #1 > > > > > > > Andrew/Qing, can you paste the generated Apis that you have for > > > both > > > > > > Scala and Java in a gist please. > > > > > > > > > > > > > > > On Sep 29, 2018, at 2:41 PM, YiZhi Liu <[email protected]> > > > wrote: > > > > > > > > > > > > > > > > Naveen, software designing is all about tradeoff, every > feature > > > we > > > > > > > > introduce causes more compiling time, more efforts to > maintain, > > > etc. > > > > > > > > > > > > > > > > The main difference is. > > > > > > > > > > > > > > > > Option #1: Java users do > > > > > > > > NDArray.BatchNorm(data, gamma, beta, null, null, null, null, > > > null, > > > > > > > > null, null, null, null, null, null); > > > > > > > > (and because every operator has an argument "out", users > need to > > > add > > > > > > > > an extra "null" to the function call almost every time.) > > > > > > > > > > > > > > > > Option #2, Java users do > > > > > > > > > > > JavaNDArray.BatchNorm(data).setGamma(gamma).setBeta(beta).invoke(); > > > > > > > > > > > > > > > > I don't think any of the reasons you listed is so important > as > > > the > > > > > > > > benefit above we got from option #2. > > > > > > > >> On Sat, Sep 29, 2018 at 8:24 AM Naveen Swamy < > > > [email protected]> > > > > > > wrote: > > > > > > > >> > > > > > > > >> Java APIs are not like Clojure - The current proposal is > only to > > > > > > build a > > > > > > > >> few thin wrappers for Inference. > > > > > > > >> > > > > > > > >> To better represent the two cases and this discussion in > > > particular, > > > > > > here > > > > > > > >> is an example API > > > > > > > >> > > > > > > > >> 1) def Activation (data : org.apache.mxnet.NDArray, > act_type : > > > > > > String, out > > > > > > > >> : Option[NDArray] = None) : > org.apache.mxnet.NDArrayFuncReturn > > > > > > > >> or > > > > > > > >> 2) def Activation (data : org.apache.mxnet.NDArray, > act_type : > > > > > > String, out > > > > > > > >> : NDArray) : org.apache.mxnet.NDArrayFuncReturn > > > > > > > >> > > > > > > > >> The discussion is should we add(generate) 200+ APIs to make > it > > > Java > > > > > > > >> compatible, ie., remove the Option class and the None > default > > > value > > > > > > which > > > > > > > >> Java does not understand from Option 1) > > > > > > > >> > > > > > > > >> my suggestion was to remove the Option class and create a > > > implicit for > > > > > > > >> backward compatibility and use null instead of None, Andrew > and > > > I > > > > > > disagreed > > > > > > > >> on this, so I suggested to raise a discussion on dev@ to > get > > > more > > > > > > opinions > > > > > > > >> and one of us will disagree and commit. Thanks for raising > it :) > > > > > > > >> > > > > > > > >> | * def Activation (data : org.apache.mxnet.NDArray, > act_type : > > > > > > String, out > > > > > > > >> : NDArray = null) : org.apache.mxnet.NDArrayFuncReturn | > > > > > > > >> -- > > > > > > > >> > > > > > > > >> 1) It is not true that Scala users will lose > *default/optional* > > > > > > arguments - > > > > > > > >> if we followed the above, they will use null or None, > though I > > > do not > > > > > > like > > > > > > > >> using nulls, this is a fine compromise. > > > > > > > >> To keep backward compatibility we can create a implicit to > > > convert > > > > > > > >> Option.None to nulls and Option.Some-> Option.get(), so you > are > > > not > > > > > > going > > > > > > > >> to break users who might have been using the APIs that were > > > released > > > > > > in > > > > > > > >> 1.3. The current incompatibility is only this w.r.t. > NDArrays. > > > > > > > >> > > > > > > > >> 2) Now about the Scala Macros - they are not simple to read > or > > > use, > > > > > > When I > > > > > > > >> and Qing started working on the #Scala Macros to improve the > > > APIs, it > > > > > > took > > > > > > > >> us a good amount of time to get a hang of it. I don't want > to > > > add > > > > > > > >> additional code when not necessary. > > > > > > > >> > > > > > > > >> My suggestion and vote is to modify existing Macro(i.e., #1 > > > from the > > > > > > > >> original email with the necessary clarification above) and > make > > > it > > > > > > > >> compatible with Java > > > > > > > >> Here are my reasons > > > > > > > >> 1) The NDArray APIs in question are not following functional > > > style of > > > > > > > >> programming, in fact they are just static methods defined > on an > > > > > > NDArray > > > > > > > >> object - so Scala users are not losing much by using null in > > > place of > > > > > > None. > > > > > > > >> You can create a implicit to maintain backward compatibility > > > > > > > >> 2) It is adding 220+ APIs(I understand it is generated) for > > > NDArray > > > > > > alone > > > > > > > >> 3) this is adding another 100s of APIs unnecessarily, we are > > > starting > > > > > > with > > > > > > > >> NDArray but we can't stop there, we will have to do this for > > > Symbol, > > > > > > > >> Executor, Iterators, etc., . > > > > > > > >> 3) I don't want to be fixing bugs and maintaining code in 2 > > > places. > > > > > > > >> 4) I want the cryptic code(# scala macros) to a minimum. > > > > > > > >> 5) increased compilation time & bad developer experience - > the > > > time to > > > > > > > >> compile has gone up quite a bit since we added the APIs last > > > release > > > > > > on my > > > > > > > >> 3 year old laptop already.. I think adding 400+ APIs > > > unnecessarily > > > > > > would > > > > > > > >> significantly increase build time and bad developer > experience > > > > > > > >> 6) I want to keep the core of the framework to be in Scala - > > > because > > > > > > it > > > > > > > >> allows you to write concise code - Yes it has a bit of > learning > > > > > > curve, not > > > > > > > >> everyone needs to know. I would rather invest in > solidifying the > > > > > > Scala APIs > > > > > > > >> and add more features in Scala(RNN, Support > > > > > > GluonHybridizedBlock...there is > > > > > > > >> quite bit of work ) - do you want to rewrite everything in > > > Scala and > > > > > > Java. > > > > > > > >> 7) Also, the discussion is not creating NDArray class for > Java, > > > just > > > > > > > >> generate certain APIs to cater for Java incompatibility. > > > > > > > >> > > > > > > > >> @Andrew: To your response to Qing's comments - you cannot > just > > > > > > consider it > > > > > > > >> as just generating NDArray's APIs and instead I suggest to > take > > > a > > > > > > wholistic > > > > > > > >> view of all the various implications. > > > > > > > >> > > > > > > > >> @Chris: Yes, Scala has a bit of learning curve - the goal > is not > > > > > > having > > > > > > > >> every developer to deal with how these APIs are generated, > > > > > > > >> the problem exists either ways with the above proposal. I > might > > > agree > > > > > > if we > > > > > > > >> were to move away completely(with a thorough discussion and > > > valid > > > > > > reasons) > > > > > > > >> and instead use AspectJ or similar to write these APIs, the > > > > > > discussion is > > > > > > > >> about using Scala Macros to generate 2 different types of > APIs > > > which > > > > > > are > > > > > > > >> functionally not different and usability wise are very very > > > similar, > > > > > > look > > > > > > > >> at the example. > > > > > > > >> Thanks for your input, I will deposit your 0.02$ in our JIRA > > > bank :) > > > > > > > >> > > > > > > > >> @Carin: It requires more effort to use AspectJ or similar to > > > generate > > > > > > APIs > > > > > > > >> using reflection or at compile time, here we need to > generate at > > > > > > compile > > > > > > > >> time so Java users have the API signature on their IDEs. > > > > > > > >> > > > > > > > >> Thanks, Naveen > > > > > > > >> > > > > > > > >> P.S: I am traveling and my responses will be delayed. > > > > > > > >> > > > > > > > >> > > > > > > > >>> On Fri, Sep 28, 2018 at 10:25 AM Carin Meier < > > > [email protected]> > > > > > > wrote: > > > > > > > >>> > > > > > > > >>> Sorry bad paste on the gist - here is the good one > > > > > > > >>> > > > https://gist.github.com/gigasquid/01cd48f563db4739910592dd9ac9db20 > > > > > > > >>> > > > > > > > >>>> On Fri, Sep 28, 2018 at 10:24 AM Carin Meier < > > > [email protected]> > > > > > > wrote: > > > > > > > >>>> > > > > > > > >>>> +1 on option #2 > > > > > > > >>>> > > > > > > > >>>> In the case of minimizing the the overhead for code > > > maintenance, I > > > > > > wanted > > > > > > > >>>> to suggest the option of investigating generating code > from > > > the Java > > > > > > > >>>> Reflection for the Java APIs. I did a quick gist from > > > Clojure of > > > > > > what > > > > > > > >>> the > > > > > > > >>>> generated classes look like from the current Scala > Symbol.api > > > for > > > > > > > >>>> FullyConnected here > > > > > > > >>>> https://gist.github.com/gigasquid/01cd48f563db4739910592 > > > > > > > >>>> > > > > > > > >>>> I looks like that there is always a base Java class > generated > > > will > > > > > > all > > > > > > > >>> the > > > > > > > >>>> arguments. If this is the case, then there is a > possibility to > > > > > > generate a > > > > > > > >>>> Java api based on this Java method automatically with > just a > > > > > > conversion > > > > > > > >>> for > > > > > > > >>>> the Scala option and it might be reusable for all the > > > packages. > > > > > > > >>>> > > > > > > > >>>> Not sure if it will work for this use case, but thought I > > > would > > > > > > bring it > > > > > > > >>>> up in case it's helpful. > > > > > > > >>>> > > > > > > > >>>> - Carin > > > > > > > >>>> > > > > > > > >>>> On Fri, Sep 28, 2018 at 7:05 AM Davydenko, Denis > > > > > > <[email protected] > > > > > > > >>>> > > > > > > > >>>> wrote: > > > > > > > >>>> > > > > > > > >>>>> +1 on option #2. Having clear Java interface for NDArray, > > > from my > > > > > > > >>>>> perspective, would be a better experience for Java users > as > > > it > > > > > > won't > > > > > > > >>>>> require them to deal with Scala code in any capacity. > > > Overhead of > > > > > > extra > > > > > > > >>>>> code for additional macros is justified, in my mind, as > it > > > will be > > > > > > > >>>>> introduced with option #1 either way, just in a different > > > place. > > > > > > > >>>>> > > > > > > > >>>>> -- > > > > > > > >>>>> Thanks, > > > > > > > >>>>> Denis > > > > > > > >>>>> > > > > > > > >>>>> On 9/27/18, 6:14 PM, "YiZhi Liu" <[email protected]> > > > wrote: > > > > > > > >>>>> > > > > > > > >>>>> I vote for "2.) Leave the existing macro in place and > add > > > another > > > > > > > >>>>> which generates a Java friendly version" > > > > > > > >>>>> > > > > > > > >>>>> @Qing @Andrew, could you give some examples, so that > people > > > can > > > > > > > >>> better > > > > > > > >>>>> understand how it provides "best possible experience" to > > > Java > > > > > > users. > > > > > > > >>>>> > > > > > > > >>>>> I have no strong preference between having JavaShape & > > > JavaContext > > > > > > > >>> or > > > > > > > >>>>> not. > > > > > > > >>>>> On Thu, Sep 27, 2018 at 5:56 PM Andrew Ayres < > > > > > > > >>>>> [email protected]> wrote: > > > > > > > >>>>>> > > > > > > > >>>>>> That's not really the conversation I'm wanting to have. > I > > > want a > > > > > > > >>>>> discussion > > > > > > > >>>>>> about the macros with respect to NDArray so that we can > get > > > > > > > >>>>> agreement on > > > > > > > >>>>>> our path forward with respect to implementing the > NDArray > > > wrapper. > > > > > > > >>>>>> > > > > > > > >>>>>> The design that was put forth and agreed to was for a a > Java > > > > > > > >>>>> wrapper around > > > > > > > >>>>>> the Scala API. Adding a bunch of Java friendly methods > > > inside the > > > > > > > >>>>> Scala > > > > > > > >>>>>> code would create a mess for users. Maintenance would be > > > > > > > >>>>> essentially the > > > > > > > >>>>>> same for both because either way you're going to be > > > updating Java > > > > > > > >>>>> methods > > > > > > > >>>>>> when you make Scala changes. > > > > > > > >>>>>> > > > > > > > >>>>>> Let's please stick with the issue in the original email. > > > > > > > >>>>>> > > > > > > > >>>>>> Thanks, > > > > > > > >>>>>> Andrew > > > > > > > >>>>>> > > > > > > > >>>>>>> On Thu, Sep 27, 2018 at 5:22 PM Qing Lan < > > > [email protected]> > > > > > > > >>>>>> wrote: > > > > > > > >>>>>> > > > > > > > >>>>>>> I would like to loop this back a layer. Current, there > is a > > > > > > > >>>>> discussion in > > > > > > > >>>>>>> the MXNet Scala community on the ways to implement the > Java > > > > > > > >>> APIs. > > > > > > > >>>>> Currently > > > > > > > >>>>>>> there are two thoughts: > > > > > > > >>>>>>> > > > > > > > >>>>>>> 1. Make Scala Java Friendly (Create Java compatible > > > methods in > > > > > > > >>>>> the Scala > > > > > > > >>>>>>> Class. such as NDArray with Java compatible > constructor) > > > > > > > >>>>>>> 2. Make Java friendly wrappers in Scala (Andrew's > > > explanation > > > > > > > >>>>> below) > > > > > > > >>>>>>> > > > > > > > >>>>>>> The first approach require minimum input from our side > to > > > > > > > >>>>> implement > > > > > > > >>>>>>> however bring user a bunch of useless api they may not > > > want to > > > > > > > >>>>> use. It also > > > > > > > >>>>>>> makes Scala package heavier. The good thing is these > two > > > > > > > >>> packages > > > > > > > >>>>> require > > > > > > > >>>>>>> minimum maintenance cost. As a tradeoff, if any time > in the > > > > > > > >>>>> future we want > > > > > > > >>>>>>> to make Java big (make Java as the primary language > > > supported by > > > > > > > >>>>> MXNet), > > > > > > > >>>>>>> then the migration from Scala to Java will be harmful. > > > Spark > > > > > > > >>>>> consider this > > > > > > > >>>>>>> carefully and decide not to change much on their Scala > > > code base > > > > > > > >>>>> to make it > > > > > > > >>>>>>> more Java. > > > > > > > >>>>>>> > > > > > > > >>>>>>> The second approach will make unique NDArray, Shape, > > > Context and > > > > > > > >>>>> more. The > > > > > > > >>>>>>> good thing about this is we can always holds a version > > > control > > > > > > > >>> on > > > > > > > >>>>> Java. > > > > > > > >>>>>>> Some breaking changes on Scala may not influence much > on > > > Java. > > > > > > > >>> It > > > > > > > >>>>> did the > > > > > > > >>>>>>> best way to decouple the module and good for us to > build > > > unique > > > > > > > >>>>> pipeline > > > > > > > >>>>>>> for Java. The bad thing with this design is the > > > maintenance cost > > > > > > > >>>>> as we need > > > > > > > >>>>>>> to keep two code bases, but it also make Java side > easy to > > > > > > > >>> change > > > > > > > >>>>> to make > > > > > > > >>>>>>> it better compatible with users. > > > > > > > >>>>>>> > > > > > > > >>>>>>> Thanks, > > > > > > > >>>>>>> Qing > > > > > > > >>>>>>> > > > > > > > >>>>>>> On 9/27/18, 3:25 PM, "Andrew Ayres" < > > > [email protected]> > > > > > > > >>>>> wrote: > > > > > > > >>>>>>> > > > > > > > >>>>>>> Hi, > > > > > > > >>>>>>> > > > > > > > >>>>>>> Currently, we're working to implement a new Java API > and > > > > > > > >>>>> would like > > > > > > > >>>>>>> some > > > > > > > >>>>>>> feedback from the community on an implementation > detail. > > > In > > > > > > > >>>>> short, the > > > > > > > >>>>>>> new > > > > > > > >>>>>>> Java API will use the existing Scala API (in a manner > > > > > > > >>> similar > > > > > > > >>>>> to how > > > > > > > >>>>>>> the > > > > > > > >>>>>>> current Clojure API works). This basically means that > > > we're > > > > > > > >>>>> making Java > > > > > > > >>>>>>> friendly wrappers to call the existing Scala API. > > > > > > > >>>>>>> > > > > > > > >>>>>>> The feedback we're looking for is on the > implementation of > > > > > > > >>>>> NDArray. > > > > > > > >>>>>>> Scala's > > > > > > > >>>>>>> NDArray has a significant amount of code which is > > > generated > > > > > > > >>>>> via macros > > > > > > > >>>>>>> and > > > > > > > >>>>>>> we've got two viable paths to move forward: > > > > > > > >>>>>>> > > > > > > > >>>>>>> 1.) Change the macro to generate Java friendly > methods - > > > To > > > > > > > >>>>> do this > > > > > > > >>>>>>> we'll > > > > > > > >>>>>>> modify the macro so that the generated methods won't > have > > > > > > > >>>>>>> default/optional > > > > > > > >>>>>>> arguments. There may also have to be some changes to > > > > > > > >>>>> parameter types to > > > > > > > >>>>>>> make them Java friendly. The big advantage here is > that > > > > > > > >>>>> ongoing > > > > > > > >>>>>>> maintenance > > > > > > > >>>>>>> will easier. The disadvantages are that we'll be > changing > > > > > > > >>> the > > > > > > > >>>>> existing > > > > > > > >>>>>>> Scala NDArray Infer API (it's marked experimental) and > > > Scala > > > > > > > >>>>> users will > > > > > > > >>>>>>> lose the ability to use the default and optional > > > arguments. > > > > > > > >>>>>>> > > > > > > > >>>>>>> 2.) Leave the existing macro in place and add another > > > which > > > > > > > >>>>> generates a > > > > > > > >>>>>>> Java friendly version - The biggest issue here is that > > > we'll > > > > > > > >>>>> be > > > > > > > >>>>>>> doubling > > > > > > > >>>>>>> the number of macros that we've got to maintain. It'll > > > > > > > >>> become > > > > > > > >>>>> even more > > > > > > > >>>>>>> overhead once we start expanding the Java API with > more > > > > > > > >>>>> classes that > > > > > > > >>>>>>> use > > > > > > > >>>>>>> generated code like this. The advantages are that the > > > > > > > >>>>> existing Scala > > > > > > > >>>>>>> NDArray Infer API would remain unchanged for Scala > users > > > and > > > > > > > >>>>> that the > > > > > > > >>>>>>> new > > > > > > > >>>>>>> macro could be optimized to give the best possible > > > > > > > >>> experience > > > > > > > >>>>> to the > > > > > > > >>>>>>> Java > > > > > > > >>>>>>> API. > > > > > > > >>>>>>> > > > > > > > >>>>>>> Thanks, > > > > > > > >>>>>>> Andrew > > > > > > > >>>>> > > > > > > > >>>>> > > > > > > > >>>>> > > > > > > > >>>>> -- > > > > > > > >>>>> Yizhi Liu > > > > > > > >>>>> DMLC member > > > > > > > >>>>> Amazon Web Services > > > > > > > >>>>> Vancouver, Canada > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > > > Yizhi Liu > > > > > > > > DMLC member > > > > > > > > Amazon Web Services > > > > > > > > Vancouver, Canada > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > > > Yizhi Liu > > > > > > DMLC member > > > > > > Amazon Web Services > > > > > > Vancouver, Canada > > > > > > > > > > > > > > > > > > > > > > > > > > > > -- > > > > Yizhi Liu > > > > DMLC member > > > > Amazon Web Services > > > > Vancouver, Canada > > > > > > > > > > > > -- > > > Yizhi Liu > > > DMLC member > > > Amazon Web Services > > > Vancouver, Canada > > > > > > > -- > Yizhi Liu > DMLC member > Amazon Web Services > Vancouver, Canada >
