How to calculate normal values of each xyz co-ordinates and ouput as a column vector for each co-ordinate?

Hi,

I have xyz point cloud data as a 40000x3 with each row containing a single point with x y and z data in the columns.

I am trying to calculate the normal value for each point to the origin, this works for an individual row, for example:

 normd = norm(data(1,:));

However I need to do it for all the rows, i used this code but it combines it into all one normal value.

 normd = norm(data(1:40000,:));

Ideally I need the normal value of each row (coordinate), in a column vector, for the range from 1 to 40000.

Thanks for any help.

Joe

Answer 1

[Matt J]

normd= sqrt( sum(data.^2,2) );

[Joe Pashley]

Thanks, not sure how this works, but it does.

[Matt J]

Not sure how it works? Isn't it virtually the definition of the norm you are trying to compute?

[Joe Pashley]

Looked at the code again and followed it step by step and understand it now, thanks.