May 17, 2005 #1 htxcrew Automotive May 17, 2005 2 I have a equation with multiple answers but I just want one solution. E.g a quadratic equation and I only want the positive result. How can I do that??
I have a equation with multiple answers but I just want one solution. E.g a quadratic equation and I only want the positive result. How can I do that??
May 17, 2005 #2 cuky2000 Electrical Aug 18, 2001 2,133 Consider using conditional statement or loops such "for", "while", if, <, > etc. Other option is obtain the solution with in a regionm contained by equation. Upvote 0 Downvote
Consider using conditional statement or loops such "for", "while", if, <, > etc. Other option is obtain the solution with in a regionm contained by equation.
May 17, 2005 #3 GregLocock Automotive Apr 10, 2001 23,435 Given that some quadratics will have two positive answers, and others have none, its a bit hard to answer, but something like biggest:max(ans1,ans2) would sort of work. Cheers Greg Locock Please see FAQ731-376 for tips on how to make the best use of Eng-Tips. Upvote 0 Downvote
Given that some quadratics will have two positive answers, and others have none, its a bit hard to answer, but something like biggest:max(ans1,ans2) would sort of work. Cheers Greg Locock Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
May 18, 2005 #4 jghrist Electrical Jul 16, 2002 4,219 The solution to a quadratic will be a vector, so using the max function as suggested by Greg should be easy. For instance: y=23·x+42·x²-32 solve for x x=-23/84+((5905+168·y)^(1/2))/84 and -23/84-((5905+168·y)^(1/2))/84 with y=456, x evaluates to a vector with elements 3.146 and -3.693. max(x)=3.146 Upvote 0 Downvote
The solution to a quadratic will be a vector, so using the max function as suggested by Greg should be easy. For instance: y=23·x+42·x²-32 solve for x x=-23/84+((5905+168·y)^(1/2))/84 and -23/84-((5905+168·y)^(1/2))/84 with y=456, x evaluates to a vector with elements 3.146 and -3.693. max(x)=3.146
May 18, 2005 Thread starter #5 htxcrew Automotive May 17, 2005 2 Hey. I just "played" with mathcad programming and came up with this: http://home1.stofanet.dk/orhan/mysuggestion.jpgIt works fine and your suggestions are also good.. Thanks Upvote 0 Downvote
Hey. I just "played" with mathcad programming and came up with this: http://home1.stofanet.dk/orhan/mysuggestion.jpgIt works fine and your suggestions are also good.. Thanks
