Re: Optimized structure of an equation
- To: mathgroup at smc.vnet.net
- Subject: [mg94564] Re: Optimized structure of an equation
- From: dh <dh at metrohm.com>
- Date: Tue, 16 Dec 2008 02:36:12 -0500 (EST)
- References: <ghtjiu$rdm$1@smc.vnet.net>
Hi,
as you want an integers solution, you formulate this as an condition
and choose a function that can take conditions like e.g. NMinimize.
Towards this you spezify the error and minimize it. Here is a simple
example that creates some data and fits a model:
d=Table[{x,x^3+x^4+Random[]},{x,1,10}];
errfun[i_,j_]=Plus@@ ((#[[1]]^i+#[[1]]^j- #[[2]])^2&/@ d);
NMinimize[{errfun[i,j],Element[{i,j},Integers]},{i,j}]
hope this helps, Daniel
Lai Ngoc Anh wrote:
> Dear all,
> I want to optimize structure of an equation as
> Z(x)=a*x^(i/6)+b*x^(j/6)+c*x^(k/6)+d*x^(m/6)+g*x^(n/6)
> in which, i, j, k, m, n are integers. The values of i, j, k, m, n are in range from 1 to 100. optimization should give the best set of i, j, k, m, n for given data Z(x).
> a, b, c, d, g are parameters to be found with the best structure form of the optimization equation the with i, j, k, m, n.
> Could you please tell me what should i do?
> thanks
>
> NA
>
>