I haven't looked very closely at your code, but a brief look reveals that
you are defining your functions in a very unusual way. Two examples:
function (f::FIRFilter)(x)
return filt(f, x)
end
function(p::pnseq)(n,T=Int64)
out = Array{T}(n)
for i in eachindex(out)
if p.count < p.width
p.cache = rand(Int64)
p.count = 64
end
out[i] = p.cache & p.mask
p.cache >>= p.width
p.count -= p.width
end
return out
end
I have never seen this way of defining them before, and I am pretty
surprised that it's not a syntax error. Long-form function signatures
should be of the form
function myfunc{T<:SomeType}(myarg1::T, myarg2)
where the type parameter section (in curly bracket) is optional.
As I said, I'm surprised it's not a syntax error, but maybe it gets parsed
as an anonymous function (just guessing here). If so, and if you are using
version 0.4, you can get slow performance.
You can read here about the right way to define functions:
http://docs.julialang.org/en/stable/manual/functions/
On Monday, September 12, 2016 at 1:32:48 PM UTC+2, Neal Becker wrote:
>
> As a first (nontrivial) try at julia, I put together some simple DSP code,
> which represents a
> pn generator (random fixed-width integer generator)
> constellation mapping
> interpolating FIR filter (from DSP.jl)
> decimating FIR filter (from DSP.jl)
> mean-square error measure
>
> Source code is here:
> https://github.com/nbecker/julia-test
>
> Profile result is here:
> https://gist.github.com/anonymous/af2459fc831ddbeb6e3be25e5c8d5197
>
> If I understand how to read this profile (not sure I do) it looks like 1/2
> the time is spent in PnSeq.jl, which seems surprising.
>
> PnSeq.jl calls rand() to get a Int64, caching the result and then
> providing
> N bits at a time to fill an Array. It's supposed to be a fast way to get
> an
> Array of small-width random integers.
>
> Most of the number crunching should be in the FIR filter functions, which
> I
> would have expected to use the most time.
>
> Anyone care to make suggestions on this code, how to make it faster, or
> more
> idiomatic Julia? I'm not proficient with Julia or with Matlab (I've been
> using python/numpy/c++ for all my work for years).
>
>
>
