determine offset point

[some one]

Does anyone know the algorithm or a function out there that will
compute the offset location given the following:
inputs:
1) x,y coordinate of starting point
2) angle (bearing)
3) distance to offset point
outputs:
1) x,y coordinate of destination

thanks

[Mark A. Odell]

fr********@yaho o.com (some one) wrote in
news:54******** *************** **@posting.goog le.com:

Does anyone know the algorithm or a function out there that will
compute the offset location given the following:
inputs:
1) x,y coordinate of starting point
2) angle (bearing)
3) distance to offset point
outputs:
1) x,y coordinate of destination

Do you have a question about the C language or did you mean to post in
comp.programmin g instead?

--
- Mark ->
--

[Joona I Palaste]

some one <fr********@yah oo.com> scribbled the following:

Does anyone know the algorithm or a function out there that will
compute the offset location given the following:
inputs:
1) x,y coordinate of starting point
2) angle (bearing)
3) distance to offset point
outputs:
1) x,y coordinate of destination

You know, for mathematics questions, there's always sci.math. Your
question is completely irrelevant to comp.lang.c. Anyway...
Suppose your variables are as follows:
1) x=x coordinate of starting point, y=y coordinate of starting point
2) theta=angle (bearing)
3) r=distance to offset point
Now the output:
x' = x coordinate of destination = x + r*cos(theta)
y' = y coordinate of destination = y + r*sin(theta)
Those formulas work right away as C expressions, given that you've
declared the variables as doubles and #included <math.h>.

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/-- Joona Palaste (pa*****@cc.hel sinki.fi) ------------- Finland --------\
\-- http://www.helsinki.fi/~palaste --------------------- rules! --------/
"The large yellow ships hung in the sky in exactly the same way that bricks
don't."
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[Martin Ambuhl]

some one wrote:

Does anyone know the algorithm or a function out there that will
compute the offset location given the following:
inputs:
1) x,y coordinate of starting point
2) angle (bearing)
3) distance to offset point
outputs:
1) x,y coordinate of destination

This is not a C question, but an elementary math question.
Even though off-topic here, the answer is short.

x_new = x_old + dist * cos(angle);
y_new = y_old + dist * sin(angle);

Since this trivial math is unknown to you, you are sure to use the wrong
measurement for the angle. Get an elementary math book and check your
documentation for the sin() and cos() function before you post a question
because you didn't express the angle in radian measure.


--
Martin Ambuhl