Programming help

[htxcrew]

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??

 

[cuky2000]

Consider using conditional statement or loops such "for", "while", if, <, > etc.

Other option is obtain the solution with in a regionm contained by equation.

 

[GregLocock]

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.

 

[jghrist]

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

 

[htxcrew]

Hey. I just "played" with mathcad programming and came up with this:

http://home1.stofanet.dk/orhan/mysuggestion.jpg

It works fine and your suggestions are also good..
Thanks