OpenEuphoria

Re: [GEN] custom_sort by ELEMENT of sequence?

• Posted by Graeme <graemeburke at CROSSWINDS.NET> Jan 14, 2001
• 461 views

At 03:22 AM 13/01/01 -0800, you wrote:
>Graeme,
>
>Jeeze, <slapping head>,
>
>I guess I've tried so hard to impress upon myself that passing values to a
>function by parameter is "cleaner" than by using global variables, I totally
>forgot about doing it with an "external" variable!  Thanks Graeme, and
>thanks also for using an *example* to explain it; even though I can
>understand it in the abstract, the example does help.
>
>But I'm still wondering if I am correct in thinking that because routine_id
>is used, one *can't* pass the element number to the sort function by
>parameter, and that there is *some*(?) reason that it has to be done via
>routine_id?
>
>Dan

Oakey-Doaky,


global function sort_by_element(integer element, sequence x)
    --99% Sort.e RDS
    integer gap, j, first, last
    object tempi, tempj

    last = length(x)
    gap = floor(last / 3) + 1
    while 1 do
        first = gap + 1
        for i = first to last do
            tempi = x[i]
            j = i - gap
            while 1 do
                tempj = x[j]
                if compare(tempi[element],tempj[element]) >= 0 then
                    j += gap
                    exit
                end if
                x[j+gap] = tempj
                if j <= gap then
                    exit
                end if
                j -= gap
            end while
            x[j] = tempi
        end for
        if gap = 1 then
            return x
        else
            gap = floor(gap / 3) + 1
        end if
    end while
end function




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