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Re: List to infix


My brute force approach would be:

ToExpression[StringReplace[ToString[mylist], ", " -> "~"]]

Cheers -- Sjoerd

On Oct 11, 11:16 am, Hugo Touchette <hugo.touche... at googlemail.com>
wrote:
> Hi,
>
> A problem about infix notation. In simple terms, I want to transform
> the list
>
> {1, Plus, 3, Times, 5, Plus, 5}
>
> into the infix form
>
> 1~Plus~3~Times~5~Plus~5
>
> to get a numerical result (here 25). Is there an easy way to do this?
> The lists I'm working with are actually much longer, so I want
> something efficient.
>
> I've tried using Infix[mylist,"~"], but the ~ there is a string, not
> the infix operator. In the end, I simply wrote
>
> ListOperation2[l_] := Module[{res, i},
>   res = l[[1]];
>   Do[
>    res = res~l[[i]]~l[[i + 1]]
>    , {i, 2, Length[l], 2}];
>   res
>   ]
>
> This works, but I thought there might be a more efficient way to do
> things.
>
> Thanks in advance for any help.
>
> oguh



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