All points except for one lie on a line. Which one is the outlier?
Example:
You are given a list of x-y pairs in a column like this:
pts = [ 0 1 0 2 3 2 0 3 0 4 ]
You would return the number 3, since the third point is the only one that is non-collinear with the other points. All the others are on the y-axis.
outlier = 3
The instructions were a bit confusing at first. It would have been better to say "Find the row number of the outlying point."
Also, using the third row as an answer and a 3 in a column of zeros makes it seem like the intent was to provide unclear instructions. (Or they are just used to writing college textbooks ;) )
The test set cases 2,3 seems to have two outliers for each case. Please check it
Uses the formula for perpendicular distance of a point to a line when the line is not axis orthogonal.
Very interesting, why the test# 3 is not passed. It turned out that the two number
(x4-x1)*(y2-y1) is not the same as (y4-y1)*(x2-x1) due to floating point. I have to compare the subtraction with 10*eps.
Very interesting. I could not understand why I had not passed the test# 3. It turned out that the two number (x4-x1)*(y2-y1) and (y4-y1)*(x2-x1) are not the same due to floating point. My choice is to compare the absolute difference with 10*eps.
I'll try to improve it!
all tests are solved test3, i don't know what is the problem
I'm sorry for this :(
I got it on solution 600827.
http://www.mathworks.com/matlabcentral/cody/problems/661-spot-the-outlier/solutions/600827
great solution
Doesn't work with outlier in first position.
Could have been MUCH smaller, but corrcoef doesn't like x=0 the first test case.
random picture with random colours
128 Solvers
Back to basics 13 - Input variables
209 Solvers
483 Solvers
Sum the numbers on the main diagonal
388 Solvers
317 Solvers