Code computing the cross-product

Posted by WizardOfOdds on Stack Overflow See other posts from Stack Overflow or by WizardOfOdds
Published on 2010-03-28T13:17:43Z Indexed on 2010/03/28 13:23 UTC
Read the original article Hit count: 315

Filed under:

math

|

cross-product

This is not a dupe of my question:

http://stackoverflow.com/questions/2532810/detecting-one-points-location-compared-to-two-other-points

If I have the following piece of pseudo-C/Java/C# code:

int a[]= { 30, 20 };
int b[] = { 40, 50 };
int c[] = {12, 12};

How do I compute the sign of the cross-product ABxAC?

I'm only interested in the sign, so I have:

boolean signABxAC = ?

Now concretely what do I write to get the sign of the cross-product ABxAC?

© Stack Overflow or respective owner

Related posts about math

how to make a function recursive

as seen on Stack Overflow - Search for 'Stack Overflow'
i have this huge function and i am wondering how to make it recursive. i have the base case which should never come true, so it should always go to else and keep calling itself with the variable t increases. any help would be great thanks def draw(x, y, t, planets): if 'Satellites' in planets["Moon"]: … >>> More
Sunrise / set calculations

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm trying to calculate the sunset / rise times using python based on the link provided below. My results done through excel and python do not match the real values. Any ideas on what I could be doing wrong? My Excel sheet can be found under .. http://transpotools.com/sun_time.xls # Created on… >>> More
Android-Java: Constructing a triangle based on Coordinates on a map and your bearing

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi Guys, I'm constructing a geolocation based application and I'm trying to figure out a way to make my application realise when a user is facing the direction of the given location (a particular long / lat co-ord). I've got the math figured, I just have the triangle to construct. //UPDATE So… >>> More
Math.max and Math.min outputting highest and lowest values allowed

as seen on Stack Overflow - Search for 'Stack Overflow'
so I'm trying to make a program that will output the sum, average, and smallest and largest values. I have everything basically figured out except the smallest and largest values are outputting 2147483647 and -2147483647, which I believe are the absolute smallest and largest values that Java will… >>> More
Is Programming == Math?

as seen on Stack Overflow - Search for 'Stack Overflow'
I've heard many times that all programming is really a subset of math. Some suggest that OO, at its roots, is mathematically based. I don't get the connection. Aside from some obvious examples: using induction to prove a recursive algorithm formal correctness proofs functional languages lambda calculus asymptotic… >>> More

Related posts about cross-product

Code computing the cross-product

as seen on Stack Overflow - Search for 'Stack Overflow'
This is not a dupe of my question: http://stackoverflow.com/questions/2532810/detecting-one-points-location-compared-to-two-other-points If I have the following piece of pseudo-C/Java/C# code: int a[]= { 30, 20 }; int b[] = { 40, 50 }; int c[] = {12, 12}; How do I compute the sign of the cross-product… >>> More
Iterate set covered by cross-product of ranges in ruby

as seen on Stack Overflow - Search for 'Stack Overflow'
I figured this answer had been asked before, so I searched, but I couldn't find anything. Granted, there are a ton of Ruby Array questions, so it might be there, just buried. In any case, I'm trying to reduce a cross-product of ranges, returning a sum of all elements of the cross-product that meet… >>> More
How to compute the cross-product?

as seen on Stack Overflow - Search for 'Stack Overflow'
I have the following piece of pseudo-C/Java/C# code: int a[]= { 30, 20 }; int b[] = { 40, 50 }; int c[] = {12, 12}; How do I compute the cross-product ABxAC? >>> More
Unity: parallel vectors and cross product, how to compare vectors

as seen on Game Development - Search for 'Game Development'
I read this post explaining a method to understand if the angle between 2 given vectors and the normal to the plane described by them, is clockwise or anticlockwise: public static AngleDir GetAngleDirection(Vector3 beginDir, Vector3 endDir, Vector3 upDir) { Vector3 cross = Vector3.Cross(beginDir… >>> More
pairwise crossproduct in Python?

as seen on Stack Overflow - Search for 'Stack Overflow'
how can I get the list of cross product pairs from a list of arbitrarily long lists in python? e.g. a = [1,2,3] b = [4,5,6] crossproduct(a,b) should yield [[1,4], [1, 5], [1,6], ...] thanks. >>> More