Discover MakerZone

MATLAB and Simulink resources for Arduino, LEGO, and Raspberry Pi

Learn more

Discover what MATLAB® can do for your career.

Opportunities for recent engineering grads.

Apply Today

Thread Subject:
multi-objective function optimization

Subject: multi-objective function optimization

From: Toan Cao

Date: 19 May, 2011 01:43:02

Message: 1 of 4

hello everyone,
i am working in small project in image processing where i need some parameters to express for my problem.
In order to find the best parameters (best solution), there is only one problem but i make 2 different functions for the same problem (the same goal ). Of course, each function is described in different way. One function has unit in pixel, another is non-unit.
When i run optimizing program, i always get false solution. I confuse whether using two different unit functions is one of reason that i receive the false solution.
can anybody help me explain for my problem ?

Subject: multi-objective function optimization

From: Alan Weiss

Date: 19 May, 2011 12:18:06

Message: 2 of 4

On 5/18/2011 9:43 PM, Toan Cao wrote:
> hello everyone,
> i am working in small project in image processing where i need some
> parameters to express for my problem.
> In order to find the best parameters (best solution), there is only one
> problem but i make 2 different functions for the same problem (the same
> goal ). Of course, each function is described in different way. One
> function has unit in pixel, another is non-unit.
> When i run optimizing program, i always get false solution. I confuse
> whether using two different unit functions is one of reason that i
> receive the false solution. can anybody help me explain for my problem ?

I am sorry, but I do not understand you.

Did you form two different optimization problems, and solve them
separately, or did you form a goal attainment problem?

Which solver did you use? How did you call it (what was the syntax)?

What exactly is unsatisfactory (what makes you think a solution is "false")?

Alan Weiss
MATLAB mathematical toolbox documentation

Subject: multi-objective function optimization

From: Toan Cao

Date: 20 May, 2011 07:39:05

Message: 3 of 4

 
> I am sorry, but I do not understand you.
>
> Did you form two different optimization problems, and solve them
> separately, or did you form a goal attainment problem?
>
> Which solver did you use? How did you call it (what was the syntax)?
>
> What exactly is unsatisfactory (what makes you think a solution is "false")?
>
> Alan Weiss

Dear Alan Weiss,

I have a problem but i design two methods for this problem. Each method is expressed by own function but they use the same variables (a variable vector consists of 4 variables).
Normally, a problem is solved by a method. However, in my case, i have two methods for one problem. Then i use the solver "fgoalattain" with goal vector: [0 0] and weight vector: [1 1]. i hope that with this way, i can obtain variable vector which reflect exactly the problem .
looking forward to your reply !
Best regards,
Toan

Subject: multi-objective function optimization

From: Alan Weiss

Date: 20 May, 2011 12:08:10

Message: 4 of 4

On 5/20/2011 3:39 AM, Toan Cao wrote:
>
>> I am sorry, but I do not understand you.
>>
>> Did you form two different optimization problems, and solve them
>> separately, or did you form a goal attainment problem?
>>
>> Which solver did you use? How did you call it (what was the syntax)?
>>
>> What exactly is unsatisfactory (what makes you think a solution is
>> "false")?
>>
>> Alan Weiss
>
> Dear Alan Weiss,
>
> I have a problem but i design two methods for this problem. Each method
> is expressed by own function but they use the same variables (a variable
> vector consists of 4 variables).
> Normally, a problem is solved by a method. However, in my case, i have
> two methods for one problem. Then i use the solver "fgoalattain" with
> goal vector: [0 0] and weight vector: [1 1]. i hope that with this way,
> i can obtain variable vector which reflect exactly the problem .
> looking forward to your reply !
> Best regards,
> Toan

I am sorry, I do not understand you.

Can you please give an example of your function calls, their returns,
and what you think is wrong?

For example,
function myobjective1 = objective1(x)
sample code here, it does not have to be your real code, but something
that can help us understand what you are doing

function myobjective2 = objective2(x)
sample code here

options = optimset(your option settings)
x = fgoalattain(your inputs)

fgoalattain messages here

***Your explanation of what is unsatisfactory here.***
***This is very important, otherwise we don't know why you are asking
for help***

Alan Weiss
MATLAB mathematical toolbox documentation

Tags for this Thread

What are tags?

A tag is like a keyword or category label associated with each thread. Tags make it easier for you to find threads of interest.

Anyone can tag a thread. Tags are public and visible to everyone.

Contact us