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Re: Drawing function with 3 variables in a graph


Hi,

> I guess my problem is still this:
> With[{m=100, a = 1}, Plot{ f[x,m], {x,-5,5}]]
>
> f contains several smaller functions, which uses a as their variable.
> But it doesn't seem like the variable a is passed on to the functions
> inside f[x,m]...

no, this is how With works: it literally replaces all occurances of m and a
in Plot{ f[x,m], {x,-5,5}]. There is no a in that expression, so you could
just as well omit the a=1 in this expression...
 
> I had hoped that this would set a = 1 and m=100, and then calculate the
> rest with x varying from -5 to 5.

If you want this, you will need Block, which _does_ set a to 1 and all
functions called from f should be using that value, too (at least if a is
not one of their "arguments"). Note that Module would not work either,
since it makes a new a (a$<somenumber> to be precise) which is different
from the a used in your other function definitions...

try this:

Block[{m=100,a=1},Plot[f[x,m],{x,-5,5}]


hth,

albert


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