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From: markspace <-@.>
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Subject: Re: Dealing with higher order operations coupled with primitives
Date: Thu, 21 Jun 2012 21:32:04 -0700
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On 6/21/2012 8:08 PM, Aaron W. Hsu wrote:

> public class IotaSumReduce {
>
>    public static int sum(int n) {
>      int res = 0;
>      for (int i = 0; i < n; i++) res += i;
        return res;
>    }


This method needed a return value; I assume you meant res.


> public class AplIotaSumReduce {
>
>    private static class Sum extends Function {
>      void apply(AplArray res, AplArray arg) {
>        Function plus = new AplArray.PlusFunction();


I think we are going to need the definitions of Function, AplArray, 
AplArray.PlusFunction, etc.  I'd prefer not to guess how you are 
implementing these right now.


>        res.iota(arg);
>        res.reduce(plus, res);

I think I understand reduction, but shouldn't it return a value?  I 
don't see how you reduce in-place like this;  are you over-writing the 
0th element or something?


>
> This program runs much much slower for me.


We'll definitely need more code.  We're far afield of what Java normally 
does.  Trying to guess at your implementation is counter productive, and 
standard ways of doing this don't exist afaik, as Java programmers don't 
normally (ever?) do this sort of thing.

I'll agree with others: Haskell/Clojure seem a better fit.