I guess Math is not my area of expertise, sorry for that :)
On Sep 15, 2010, at 7:41 PM, DanH wrote:
Yeah atan2 is a really new concept -- invented maybe 1965 with
Fortran, if not before. Pretty much a standard in all language math/
trig suites since then.
http://en.wikipedia.org/wiki/Atan2
On Sep 15, 11:56 am, Pedro Teixeira <[email protected]> wrote:
Geez this is even better than I expected. I was worried with negative
values hence the Math.abs and I wasn't sure how to express in
degrees.
Thank you very much for your answers guys, the atan2 is completely
new
to me ;)
Thanks again
On Sep 15, 2010, at 5:50 PM, Kostya Vasilyev wrote:
Um, no.
Math.atan2 takes two values, not one.
Math.atan2(y2 - y1, x2 - x1)
This gives correct result even for x2 and x1 being very close to
each other. Depending on the sign of y2 - y1 that's either "up" or
"down".
-- Kostya
15.09.2010 20:45, Robert Green пишет:
Kostya hit it:
float angleDegrees = Math.toDegrees(Math.atan2((y1 - y2) / (x1 -
x2)));
On Sep 15, 11:32 am, Kostya Vasilyev<[email protected]> wrote:
Pedro,
Java (and pretty much any language's) trig functions work with
angles
expressed in radians.
http://en.wikipedia.org/wiki/Radian
To convert to degrees, multiply by 180 / 3,1415926.... (in Java,
that's
Math.PI). Or just call Math.toDegrees.
Better yet - use Math.atan2 ( difference along Y, different along
X).
This one correctly handles the case of value3-value4 being zero
(or very
close thereof).
-- Kostya
15.09.2010 20:22, Pedro Teixeira пишет:
Hi,
I'm having problems with JAva and trigonometry to calculate a
direction from a point to a certain point...
I want to translate this equation to Java-wise:
tg^-1 = |value1-value2| / |value3-value4|
And I'd like the result in degrees.. how can I do this? any
ideia?
--
Kostya Vasilyev -- WiFi Manager + pretty widget --http://kmansoft.wordpress.com
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