Re: An Array of Equation Parameters
- To: mathgroup at smc.vnet.net
- Subject: [mg59903] Re: [mg59861] An Array of Equation Parameters
- From: "David Park" <djmp at earthlink.net>
- Date: Thu, 25 Aug 2005 06:33:36 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
Asa,
You can separate 'parameters' from 'variables' in a function definition as
in the following simple definition.
f[a_, b_][x_, y_] := a x + b y
f[2, 3][x, y]
2 x + 3 y
Now if you had a list of parameters such as...
parmlist = {{a, b}, {2, 3}, {Sin[t], Cos[t]}};
You could thread them into your function by...
MapThread[(f @@ #)[x, y] &, {parmlist}]
{a x + b y, 2 x + 3 y, y Cos[t] + x Sin[t]}
Or if you had a table of parm values...
parmarray = Table[{a, b}, {a, 1, 3}, {b, 1, 3}];
You could map the function onto the array at level 2.
Map[(f @@ #)[x, y] &, parmarray, {2}]
{{x + y, x + 2 y, x + 3 y}, {2 x + y, 2 x + 2 y, 2 x + 3 y}, {3 x + y,
3 x + 2 y, 3 x + 3 y}}
David Park
djmp at earthlink.net
http://home.earthlink.net/~djmp/
From: acvwilson at gmail.com [mailto:acvwilson at gmail.com]
To: mathgroup at smc.vnet.net
This seems like a fairly easy problem in other languages but I can't
figure out how to do it in Mathematica.
I am trying to set up an array of equation parameters, where each entry
in the array is a list of parameters for a function. I also don't know
how to get values out of a list to plug into the function. If anyone
knows how to solve this problem please help me out.
Thanks,
Asa