In 1980 I made a program for passing the diagram of activities for a large
project, computing duration and cost of the project, based on durations and
costs of the activities.
In PERT you have a record per node and a record per edge in the graph. I didn't
do it that way. I still had a record per node but no record describing the
edges. Rather the numbering of the nodes defined the edges.
This numbering is documented here. ORDINAL FRACTIONS - the algebra of data
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ORDINAL FRACTIONS - the algebra of data
This paper was submitted to the 10th World Computer Congress, IFIP 1986
conference, but rejected by the referee.... | |
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The numbering of activities is such that activities 1 and 2 are in series and
11 and 12 are in parallel and so on. I used 11-figure ordinal fractions where
the odd-numbered digit positions indicated series and even-numbered digit
positions indicated parallel.
Of cause the durations of activities in series must be added together, (+/) and
durations of activities in parallel must be maxed together (>./).
This is the smarter way to handle activity diagrams.
Thanks.
Bo
Den 3:31 onsdag den 29. november 2017 skrev Daniel Lyons
<[email protected]>:
> On Nov 28, 2017, at 7:11 PM, Henry Rich <[email protected]> wrote:
>
> You're right about the last bit - you can't start with a transitive closure.
> I missed that.
>
> Suppose you turn each dependency into a J sentence, say
>
> a =: 5
>
> or
>
> c =: longerof (a , b)
>
> or
>
> f =: a following (e , g)
>
> or combinations thereof. There must be no loops in the dependencies, so you
> could do a topological sort on the tasks, to ensure that each assignment
> refers only to names that have already defined. Then just execute the sorted
> script and see the results.
>
> You would need the definitions
>
> longerof =: >./
> following =: +
>
> and you need a topological sort, which isn't too hard. I know I wrote one
> for the Advent of Code problems a couple of years ago.
That's kind of a cool idea. Is it commonly done, generating a block of code in
a string and evaluating it?
--
Daniel Lyons
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