       Re: Very very basic question about Mathematica

• To: mathgroup at smc.vnet.net
• Subject: [mg111147] Re: Very very basic question about Mathematica
• From: Bob Hanlon <hanlonr at cox.net>
• Date: Thu, 22 Jul 2010 05:40:51 -0400 (EDT)

```You are not dealing with strings. You are using symbols and expressions and none of the expressions happen to involve strings.

Manipulate is a scoping construct. Since you want s to depend on the control, bring the definition of s within the Manipulate's scope.

Manipulate[
s = x + h;
Plot[s, {x, 0, h},
PlotRange -> {{0, 1}, {0, 2}}],
{h, 0.1, 1}]

Bob Hanlon

---- Sam Takoy <sam.takoy at yahoo.com> wrote:

=============
Hi,

I find that I don't understand a very basic thing about the building
blocks of Mathematica.

When the first command is

s = x + h

I figured that (string?) "s" represents (string?) "x+h".

This theory pans out when one tries

s^2

or

D[s, x]

or

Integrate[s, {x, 0, h}]

and

s /. h -> 1

But then by doesn't this work:

Manipulate[ Plot[s, {x, 0, h}], {h, 0.1, 1}]