comparing numbers in matlab

Question

I am trying to classify some data based on euclidean distances in matlab the only problem is that matlab is giving me numbers that look like these as distances

0 + 4.9713i
0 + 7.8858i

 num1<num2  
 num2<num1

both return 0. how is this possible?

Jonas · Accepted Answer · 2010-06-30 19:29:49Z

3

The numbers you're getting are imaginary numbers. You should never obtain imaginary numbers when you calculate Euclidean distances.

Check that your Euclidean distances are correct, such as

distance=sqrt(deltaX.^2 + deltaY.^2)

If you're really sure that your distances should be complex numbers, make the comparison using e.g. the norm, i.e.

norm(num2) > norm(num1)

This evaluates to true for me.

answered Jun 30, 2010 at 19:29

Jonas

75.1k10 gold badges139 silver badges180 bronze badges

Sign up to request clarification or add additional context in comments.

Comments

MatlabDoug · Accepted Answer · 2010-06-30 20:37:49Z

1

Numbers with real and imaginary parts are not orderable. Maybe you mean order by distance from origin?

answered Jun 30, 2010 at 20:37

MatlabDoug

5,6941 gold badge26 silver badges36 bronze badges

Collectives™ on Stack Overflow

comparing numbers in matlab

2 Answers 2

Comments

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

Comments

Comments

Your Answer

Sign up or log in

Post as a guest

Related