It seems Base.maxabs was added (by Dahua) as late as May 30 
- 
https://github.com/JuliaLang/julia/commit/78bbf10c125a124bc8a1a25e8aaaea1cbc6e0ebc

If you update your Julia to the latest master, you'll have it =)

// T

On Tuesday, June 17, 2014 10:20:05 AM UTC+2, Florian Oswald wrote:
>
> Hi Dahua,
> I cannot find Base.maxabs (i.e. Julia says Base.maxabs not defined)
>
> I'm here:
>
> julia> versioninfo()
> Julia Version 0.3.0-prerelease+2703
> Commit 942ae42* (2014-04-22 18:57 UTC)
> Platform Info:
>   System: Darwin (x86_64-apple-darwin12.5.0)
>   CPU: Intel(R) Core(TM) i5-2435M CPU @ 2.40GHz
>   WORD_SIZE: 64
>   BLAS: libgfortblas
>   LAPACK: liblapack
>   LIBM: libopenlibm
>
> cheers
>
> On Monday, 16 June 2014 17:13:44 UTC+1, Dahua Lin wrote:
>>
>> First, I agree with John that you don't have to declare the types in 
>> general, like in a compiled language. It seems that Julia would be able to 
>> infer the types of most variables in your codes.
>>
>> There are several ways that your code's efficiency may be improved:
>>
>> (1) You can use @inbounds to waive bound checking in several places, such 
>> as line 94 and 95 (in RBC_Julia.jl)
>> (2) Line 114 and 116 involves reallocating new arrays, which is probably 
>> unnecessary. Also note that Base.maxabs can compute the maximum of absolute 
>> value more efficiently than maximum(abs( ... ))
>>
>> In terms of measurement, did you pre-compile the function before 
>> measuring the runtime?
>>
>> A side note about code style. It seems that it uses a lot of Java-ish 
>> descriptive names with camel case. Julia practice tends to encourage more 
>> concise naming.
>>
>> Dahua
>>
>>
>>
>> On Monday, June 16, 2014 10:55:50 AM UTC-5, John Myles White wrote:
>>>
>>> Maybe it would be good to verify the claim made at 
>>> https://github.com/jesusfv/Comparison-Programming-Languages-Economics/blob/master/RBC_Julia.jl#L9
>>>  
>>>
>>> I would think that specifying all those types wouldn’t matter much if 
>>> the code doesn’t have type-stability problems. 
>>>
>>>  — John 
>>>
>>> On Jun 16, 2014, at 8:52 AM, Florian Oswald <florian...@gmail.com> 
>>> wrote: 
>>>
>>> > Dear all, 
>>> > 
>>> > I thought you might find this paper interesting: 
>>> http://economics.sas.upenn.edu/~jesusfv/comparison_languages.pdf 
>>> > 
>>> > It takes a standard model from macro economics and computes it's 
>>> solution with an identical algorithm in several languages. Julia is roughly 
>>> 2.6 times slower than the best C++ executable. I was bit puzzled by the 
>>> result, since in the benchmarks on http://julialang.org/, the slowest 
>>> test is 1.66 times C. I realize that those benchmarks can't cover all 
>>> possible situations. That said, I couldn't really find anything unusual in 
>>> the Julia code, did some profiling and removed type inference, but still 
>>> that's as fast as I got it. That's not to say that I'm disappointed, I 
>>> still think this is great. Did I miss something obvious here or is there 
>>> something specific to this algorithm? 
>>> > 
>>> > The codes are on github at 
>>> > 
>>> > https://github.com/jesusfv/Comparison-Programming-Languages-Economics 
>>> > 
>>> > 
>>>
>>>

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