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Author Solving Equations
Mike

2005-04-26, 4:04 pm

I need to solve an equation with two unknowns

unknown1=unknown2+y

but unknown2 has to be a value such that unknown1, when put into
another equation:

unknown3=unknown1+z

gives a value for unknown3 within some range for unknown3.

Any ideas? Thanks.
Scott Dorsey

2005-04-26, 4:04 pm

In article <ef040dd.-1@webx.raydaftYaTP>, Mike <pgmbact@aol.com> wrote:
>I need to solve an equation with two unknowns
>
>unknown1=unknown2+y
>
>but unknown2 has to be a value such that unknown1, when put into
>another equation:
>
>unknown3=unknown1+z
>
>gives a value for unknown3 within some range for unknown3.
>
>Any ideas? Thanks.


This is a high school algebra problem, not a Matlab problem. Check the
Schaum's Outline of College Algebra, and look for "simultaneous equations."
You can probably use the substitution method in this case.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
Mike

2005-04-26, 4:04 pm

Scott Dorsey wrote:
>
>
> In article <ef040dd.-1@webx.raydaftYaTP>, Mike

<pgmbact@aol.com>
> wrote:
>
> This is a high school algebra problem, not a Matlab problem. Check
> the
> Schaum's Outline of College Algebra, and look for "simultaneous
> equations."
> You can probably use the substitution method in this case.
> --scott
> --
> "C'est un Nagra. C'est suisse, et tres, tres precis."
>

It very well may be, but not in terms of solving it quickly in the
application I need it for. Any kind of loop to do this takes forever.
Assume for a moment that looping through values takes at least a few
hours. Is there a faster way to do this like some sort of function in
matlab like find, fzero, etc.
Scott Dorsey

2005-04-26, 4:04 pm

>Scott Dorsey wrote:
><pgmbact@aol.com>
>It very well may be, but not in terms of solving it quickly in the
>application I need it for. Any kind of loop to do this takes forever.
>Assume for a moment that looping through values takes at least a few
>hours. Is there a faster way to do this like some sort of function in
>matlab like find, fzero, etc.


No, take both equations and get them into closed form by hand, then
implement the combined equation in Matlab.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."
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