Without looking up the source of that formula (i.e., just based on what you wrote), I determine this: that in order for the result of multiplication to be negative, one of the terms containing subtraction must be negative. In order for that to occur, one side of your triangle is longer than the sum of the other two. That is impossible. Check your parameters.
P. >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:flashcoders- >> [EMAIL PROTECTED] On Behalf Of Jordan Snyder >> Sent: Thursday, December 14, 2006 11:36 AM >> To: Flashcoders mailing list >> Subject: Re: Re: [Flashcoders] Area of a triangle using perimiter values >> only >> >> I recind half of what I said after actually thinking about it, but >> maybe it's a different perspective ;) >> >> >> On 12/14/06, Jordan Snyder <[EMAIL PROTECTED]> wrote: >> > To dodge your question, couldn't you just use the simple distance >> > forumula to determine the base even when it's not horizontal? I dont' >> > know much about your application or if you'll have the points where >> > the triangle's points lie, but that's just an idea. >> > >> > Oh, but I just thought of something from my old rusty brain. I looked >> > at the formula on the mathworld page; would that not indicate a >> > distributive method of multiplication? Again, rusty, but a thought. >> > >> > Let us know what you figure out!! >> > >> > >> > Cheers >> > >> > On 12/14/06, Merrill, Jason <[EMAIL PROTECTED]> wrote: >> > > I'm trying to figure the area of a triangle in Actionscript using the >> > > perimeter values only, not the traditional simple formula: >> > > >> > > area = (height/2)*base >> > > >> > > because figuring the height is tricky given the triangle will be >> drawn >> > > in odd ways (i.e. a not horizontally alinged base), so I am exploring >> > > other triangle area forumulas that only take in the perimiter values >> > > (a,b,c), like Heron's formula or this one, which I like: >> > > >> > > given a,b,c are the length of the sides of the triangle, then the >> > > formula is: >> > > >> > > squareRoot of: (a+b+c)(b+c-a)(c+a-b)(a+b-c) >> > > _______________________________________ >> > > 4 >> > > >> > > So in trying to translate that to actionscript, I wrote: >> > > >> > > public static function areaOfTriangle(a:Number, b:Number, >> > > c:Number):Number{ >> > > return (Math.sqrt((a+b+c)*(b+c-a)*(c+a-b)*(a+b- >> c)))/4; >> > > } >> > > >> > > But the problem is (a+b+c)*(b+c-a)*(c+a-b)*(a+b-c) results in a >> negative >> > > number, and this the square root cannot be taken. Or perhaps I am >> > > interpreting the forumula incorrectly: >> > > http://mathworld.wolfram.com/TriangleArea.html >> > > >> > > What am I doing wrong here? Thanks. >> > > >> > > Jason Merrill >> > > Bank of America >> > > Learning & Organizational Effectiveness >> > > >> > > >> > > >> > > >> > > _______________________________________________ >> > > Flashcoders@chattyfig.figleaf.com >> > > To change your subscription options or search the archive: >> > > http://chattyfig.figleaf.com/mailman/listinfo/flashcoders >> > > >> > > Brought to you by Fig Leaf Software >> > > Premier Authorized Adobe Consulting and Training >> > > http://www.figleaf.com >> > > http://training.figleaf.com >> > > >> > >> > >> > -- >> > Jordan Snyder >> > jordansnyder.com >> > Applications Developer >> > Image Action LLC >> > http://www.imageaction.com >> > >> >> >> -- >> Jordan Snyder >> Applications Developer >> Image Action LLC >> http://www.imageaction.com >> _______________________________________________ >> Flashcoders@chattyfig.figleaf.com >> To change your subscription options or search the archive: >> http://chattyfig.figleaf.com/mailman/listinfo/flashcoders >> >> Brought to you by Fig Leaf Software >> Premier Authorized Adobe Consulting and Training >> http://www.figleaf.com >> http://training.figleaf.com _______________________________________________ Flashcoders@chattyfig.figleaf.com To change your subscription options or search the archive: http://chattyfig.figleaf.com/mailman/listinfo/flashcoders Brought to you by Fig Leaf Software Premier Authorized Adobe Consulting and Training http://www.figleaf.com http://training.figleaf.com
