Re: FindMinimum
- To: mathgroup at smc.vnet.net
- Subject: [mg15866] Re: FindMinimum
- From: "Hossein Kazemi" <kazemi at som.umass.edu>
- Date: Fri, 12 Feb 1999 18:40:27 -0500 (EST)
- Organization: University of Massachusetts, Amherst
- References: <79m6o0$3at@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Sorry, I just noticed an error in my presentation of the problem. The
correct for is:
f=Sign[4.35x-13.57y +Sqrt[1-x^2-y^2]] - Sign[2.49x-11.18y+
Sqrt[1-x^2-y^2]]+...
Hossein Kazemi wrote in message <79m6o0$3at at smc.vnet.net>...
>I have an expression that involves the Sign[] function. For example,
>consider
>
>f=Sign[4.35x-13.57y +(1-x^2-y^2)]-Sign[2.49x-11.18y+(1-x^2-y^2)]+...
>
>I need to find the minimum of this function. Since the symbolic
>derivatives with respect to x and y do not exist, I have to use
>
>FindMinimum[f,{x,{x0,x1}},{y,{y0,y1}}]
>
>But this does not restrict Mathematica not look outside (-1,1) range for
>solutions,
>where (1 - x^2 - y^2) will not be real.
>
>Is there anyway to find the minimum of a function when symbolic
>derivatives of
>the function do not exist and values outside a range should not be used.
>
>Thank you.
>kazemi at som.umass.edi
>
>
>