Re: Input pattern

[Ole Tange]

On Mon, Mar 21, 2016 at 4:37 PM, Ali Roustaei <ali.rostai@gmail.com> wrote:
> Hello,
>
> My script (say myscript) has three input parameters H, Re and Bn. Re and Bn
> are tied so that for each Re input there is only a specific Bn.
>
> I want parallel to run all combinations of H with Bn,Re and not generate
> combinations between Re and Bn. In terms of gnu parallel I want -xapply for
> Re, Bn and usual combination for H with them.
>
> For example the below shows what I would like parallel to run. Imagine the
> inputs:
>
> H inputs: A B
> Re inputs: C D E
> Bn inputs: F G H
> (So  C corresponds to F, D to G and E to H)
>
> myscript A C F
> myscript A D G
> myscript A E H
>
> myscript B C F
> myscript B D G
> myscript B E H

Currently this is not possible using a single command, but I have had
this problem, too, so I would welcome a patch that made it possible.

My suggestion for syntax would be to introduce a modifier on the
argument separator. Something like +:

  parallel myscript ::: A B ::: C D E :::+ F G H

And if the input source is a file:

  parallel myscript ::: A B ::: C D E ::::+ fgh-file

The idea being that :::+ links the following input source to the
previous --xapply style.

Normal --xapply would then be possible to do like this:

  parallel myscript ::: C D E :::+ F G H

For your current situation this may work:

  parallel --xapply -I ,, --arg-sep ,,, parallel eval echo myscript {}
,, ::: A B ,,, C D E ,,, F G H

/Ole