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From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: sym and solve
Date: Mon, 16 Jan 2012 12:16:09 +0000 (UTC)
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Xref: news.mathworks.com comp.soft-sys.matlab:754803

"Roger Stafford" wrote in message <jf06ph\$cce\$1@newscl01ah.mathworks.com>...
>  theta = atan2(t,s);
> ........
>  x1 = u*cos(theta)-v*sin(theta);
>  y1 = u*sin(theta)+v*cos(theta);
>  x2 = u*cos(theta)+v*sin(theta);
>  y2 = u*sin(theta)-v*cos(theta);
- - - - - - - - - -
In that suggestion I made to you there really was no need for explicitly evaluating theta with 'atan2' and then finding cos(theta) and sin(theta).  I don't know why I did that.  It is much simpler to just use (s/a) in place of cos(theta) and (t/a) in place of sin(theta) in transforming (u,v) over to (x1,y1) and (x2,y2).

Roger Stafford
```