Using the sqrt(r^2-x^2) formula I get the same results as with the [sin], [cos]. Maybe I'm just implementing it wrong, but I can't figure out why it's not plotting the correct y values...<div><br></div><div>Here's the patch I sent before with my implementation of the sqrt(r^2 - x^2)</div>
<div><br><div class="gmail_quote">On Sun, Apr 10, 2011 at 8:52 AM, Mathieu Bouchard <span dir="ltr"><<a href="mailto:matju@artengine.ca">matju@artengine.ca</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">
<div class="im">On Sun, 10 Apr 2011, Tyler Leavitt wrote:<br>
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<blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
I've not had any real success using the formulas with [sin] and [cos]...<br>
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I don't know why, but I had assumed that you wanted to plot something "parametrically", such as a path drawn from x(t) and y(t) functions, instead of a y(x) function. I was reading too fast.<br>
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For a y(x) function, sqrt(r*r-x*x) is the formula to use.<br>
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That is related to the fact that sqrt(1-x*x) = sin(acos(x)) = cos(asin(x)) where asin is anti-sin and acos is anti-cos.<br>
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It's also related to Pythagoras' theorem x*x + y*y = r*r which is also sin(t)*sin(t) + cos(t)*cos(t) = 1.<div><div></div><div class="h5"><br>
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| Mathieu Bouchard ---- tél: <a href="tel:%2B1.514.383.3801" value="+15143833801" target="_blank">+1.514.383.3801</a> ---- Villeray, Montréal, QC<br>
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