[julia-users] Generic FloatingPoint-Integer DRY?

[Michael Fox]

It's kind of painful to see codes repeating themselves like this. Here's 
one I just ran across in `statistics.jl`. Is there something about the type 
or dispatch system that encourages or even requires such repetition? Can 
you think of a better idea?

## nice-valued ranges for histograms
function histrange{T<:FloatingPoint,N}(v::AbstractArray{T,N}, n::Integer)
    if length(v) == 0
        return Range(0.0,1.0,1)
    end
    lo, hi = minimum(v), maximum(v)
    if hi == lo
        step = 1.0
    else
        bw = (hi - lo) / n
        e = 10.0^floor(log10(bw))
        r = bw / e
        if r <= 2
            step = 2*e
        elseif r <= 5
            step = 5*e
        else
            step = 10*e
        end
    end
    start = step*(ceil(lo/step)-1)
    Range(start,step,1+iceil((hi - start)/step))
end

function histrange{T<:Integer,N}(v::AbstractArray{T,N}, n::Integer)
    if length(v) == 0
        return Range(0,1,1)
    end
    lo, hi = minimum(v), maximum(v)
    if hi == lo
        step = 1
    else
        bw = (hi - lo) / n
        e = 10^max(0,ifloor(log10(bw)))
        r = bw / e
        if r <= 1
            step = e
        elseif r <= 2
            step = 2*e
        elseif r <= 5
            step = 5*e
        else
            step = 10*e
        end
    end
    start = step*(iceil(lo/step)-1)
    Range(start,step,1+iceil((hi - start)/step))
end