Maximum absolute value in array

I have a formula carry out a calculation that gives me positive and negative numbers (which is is supposed to) that correspond to an alpha angle. How can I find the maximum asbsolute value and find its corresponding alpha?

My code it

By = round((Ey-(FGH.*sind(gamma))),5);
Bymax = max(abs(By))
indexes = find(By == Bymax);
angleBy = alpha(indexes)

Where my Bymax is originally negative but the abs turns it positive. Now I need to find teh corresponding alpha to the Bymax.

It gives me:

angleBy =

  1×0 empty double row vector

I tried with another force I have that the magnitude is already a positive number.. the code looks like:

Bz = Ez+(FGH.*cosd(gamma));
Bzmax = max(abs(Bz))
indexes = find(Bz == Bzmax);
angleBz = alpha(indexes)

And that gives me:

Bzmax =

       3801.5


angleBz =

        8.686

Which is what I want.

What am I doing wrong?

Answer 1

[Jan]

Use the 2nd output of the max() command:

[Bymax, index] = max(abs(By))
By(index)