Re: display of function
- To: mathgroup at smc.vnet.net
- Subject: [mg58531] Re: [mg58506] display of function
- From: "Carl K. Woll" <carl at woll2woll.com>
- Date: Wed, 6 Jul 2005 03:11:15 -0400 (EDT)
- References: <200507050557.BAA29432@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Darrell Bosch wrote:
>
> Dear Math Group:
>
> The first equation below shows a function for u(y) which is
> the sum of the products of pi times yi. In the following steps, I
> assign values of p and y. How can I get Mathematica to display the
> numerical value of u for the given p and y values? When I insert the
> u[y] command, I just get a repeat of the equation I have entered.
> Thanks for your suggestions. This group is a great help. Darrell
>
>
>
> u[y_] := Sum[Subscript[p, i]*Subscript[y, i],
>
> {i, 1, n}]
>
>
>
> p = {.3,.4,.3}
>
>
>
> y={10000, 20000, 30000}
>
>
Darrell,
As others have mentioned, for this case the simplest approach is to use Dot:
u[y_] := p.y
Again, as others have mentioned, using Part instead of Subscript in your
method would work.
I just want to point out that it's possible to use subscripts in the way you
intended:
u[y_] := Sum[ p * y ,{i,1,n}]
[[i]] [[i]]
The above is not working Mathematica code, you need to use 2D boxform input,
i.e., input the subscripts using Ctrl-_. In other words, when Mathematica
parses 2D boxform input where the subscript is a part specfication, then
Part is automatically used instead of Subscript. You can make things even
prettier by using \[LeftDoubleBracket] and \[RightDoubleBracket] instead of
[[ and ]].
Carl Woll
Wolfram Research
- References:
- display of function
- From: "Bosch, Darrell" <bosch@vt.edu>
- display of function