Re: Usage of "//" Operator
- To: mathgroup at smc.vnet.net
- Subject: [mg45270] Re: Usage of "//" Operator
- From: drbob at bigfoot.com (Bobby R. Treat)
- Date: Wed, 24 Dec 2003 17:42:28 -0500 (EST)
- References: <bsbmmj$lqc$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
This is in the right form, at least:
tb = Table[0, {i, 1, 10}, {j, 1, 10}] // MatrixForm // Extract[#, {1}] &
This also works:
Table[0, {i, 1, 10}, {j, 1, 10}] // MatrixForm
%
or this:
Table[0, {i, 1, 10}, {j, 1, 10}] // MatrixForm // First
or... since you don't want MatrixForm anyway, just...
Table[0, {i, 1, 10}, {j, 1, 10}]
Bobby
Harold.Noffke at wpafb.af.mil (Harold Noffke) wrote in message news:<bsbmmj$lqc$1 at smc.vnet.net>...
> Hello.
>
> The following code will produce the result of "beheading" MatrixForm
> from a 10x10 nested List of "0" elements ...
>
> [1] tb = Table[0, {i, 1, 10}, {j, 1, 10}] // MatrixForm;
> Extract[tb, {1}]
>
> However, if I change [1] to include a second "//" to accomplish the
> same thing, I get this ...
>
> [2] tb = Table[0, {i, 1, 10}, {j, 1, 10}] // MatrixForm //
> Extract[<?>, {1}]
>
> This does not work at all, no matter what I use to replace the "<?>",
> which is just my ad-hoc symbol for, "I don't know what to put here."
>
> When I look in the Mathematica index of Operator Input Forms, I find
> ...
>
> [3] expr1 // expr2 == expr2[expr1]
>
> The "==" in [3] is another ad-hoc symbol of mine, which means Operator
> Form "is the same as" FullForm.
>
> Now we get to my puzzlement. If expr2 takes multiple arguments, how
> do we denote the results of evaluating expr1, as in my "<?>" in [2]?
>
> Thanks for any help or clarifications on this. My best guess at the
> moment is that Mathematica has no way to do this, which would make
> "expr1 // expr2" be NOT fully equivalent to "expr2[expr1]".
>
> Harold