Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to microsoft.public.excel.programming
external usenet poster
 
Posts: 1
Default Is Solver Modification Possible? PLEASE HELP!

I have an equation I am attempting to fit to some data via 2 variable
constants. However, my equation can't be solved directly. I CAN solve
this equation for my data result variable, but I have to use goalseek
or solver. I want to perform a minimization of a sum of the square of
the differences of my data values and my data result variable. To do
this I would need to imbed a goalseek or solver within the Excel Solver
code. Can anyone help me?
  #2   Report Post  
Posted to microsoft.public.excel.programming
external usenet poster
 
Posts: 19
Default Is Solver Modification Possible? PLEASE HELP!

What are "variable constants?" And what does it mean to
"[embed]...Solver within the Excel Solver code?"

It seems you want to fit a linear function to some data. If so, look
up XL help for the LINEST function.

--
Regards,

Tushar Mehta, MS MVP -- Excel
www.tushar-mehta.com
Excel, PowerPoint, and VBA add-ins, tutorials
Custom MS Office productivity solutions

In article ,
says...
I have an equation I am attempting to fit to some data via 2 variable
constants. However, my equation can't be solved directly. I CAN solve
this equation for my data result variable, but I have to use goalseek
or solver. I want to perform a minimization of a sum of the square of
the differences of my data values and my data result variable. To do
this I would need to imbed a goalseek or solver within the Excel Solver
code. Can anyone help me?

  #3   Report Post  
Posted to microsoft.public.excel.programming
external usenet poster
 
Posts: 1
Default Is Solver Modification Possible? PLEASE HELP!

On Mon, 1 Sep 2003 21:12:59 -0400, ChemEstudent
wrote in
microsoft.public.excel.programming:

I have an equation I am attempting to fit to some data via 2 variable
constants. However, my equation can't be solved directly. I CAN solve
this equation for my data result variable, but I have to use goalseek
or solver. I want to perform a minimization of a sum of the square of
the differences of my data values and my data result variable. To do
this I would need to imbed a goalseek or solver within the Excel Solver
code. Can anyone help me?


Create a reference to SOLVER.XLA, then look at the objects in the
Object Browser (F2) for the library SOLVER, or use a recorded macro as
a starting point.

--
Michael Bednarek, IT Manager, Tactical Global Management
Waterfront Pl, Brisbane 4000, Australia. "POST NO BILLS"
http://mcmbednarek.tripod.com/
  #4   Report Post  
Posted to microsoft.public.excel.programming
external usenet poster
 
Posts: 1
Default Is Solver Modification Possible? PLEASE HELP!

If I understand your problem, you have n observations where each observation
consists of a y value and one or more x values (x1, x2, ...). the x's and y
are related by a implicit function 0=f(y,x1,x2,...,b1,b2) where b1 and b2
are your parameters. You can solve this problem using solver by creating n
equality constraints (one for each observation) between a hypothetical value
of y, the observed x values, and the parameter values. The objective value
to be minimized is the sum of the squares difference between the observed y
values and the hypothetical y values. The "By changing cells" entry for
solver is the set of hypothetical y cells and the parameter cells. Using
this method, solver will simultaneously solve your equation for y and find
the "best" values for your parameters.

Neal


"ChemEstudent" wrote in message
...
I have an equation I am attempting to fit to some data via 2 variable
constants. However, my equation can't be solved directly. I CAN solve
this equation for my data result variable, but I have to use goalseek
or solver. I want to perform a minimization of a sum of the square of
the differences of my data values and my data result variable. To do
this I would need to imbed a goalseek or solver within the Excel Solver
code. Can anyone help me?



Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Formula modification yshridhar Excel Worksheet Functions 10 November 23rd 07 08:16 AM
Formula Modification No Name Excel Discussion (Misc queries) 2 May 1st 07 03:33 AM
last modification Chip Smith Excel Discussion (Misc queries) 1 June 19th 06 11:55 PM
Interesting Solver problem (Solver encounters an error) MrShorty Excel Discussion (Misc queries) 3 December 22nd 05 10:52 PM
Macro modification Hirsch Excel Discussion (Misc queries) 3 May 27th 05 10:21 PM


All times are GMT +1. The time now is 12:24 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 ExcelBanter.
The comments are property of their posters.
 

About Us

"It's about Microsoft Excel"