How to get norm (magnitude) of a vector the simple way?

5 views (last 30 days)
I just want to get the norm of
syms phi the;
c = [-cos(phi)*sin(the)^2;-sin(phi)*sin(the)^2; - cos(the)*sin(the)*cos(phi)^2 - cos(the)*sin(the)*sin(phi)^2]
norm(c,2)
isn't really simplifying anything
If I type it manually:
simplify(sqrt(cos(phi)^2*sin(the)^4+sin(phi)^2*sin(the)^4+sin(the)^2*cos(the)^2))
I get a simple answere:
(sin(the)^2)^(1/2)
  5 Comments
Niklas Kurz
Niklas Kurz on 8 May 2021
I'm sorry for forgetting the simicolons in c. It might have been hard for you to reproduce what I was trying to create.

Sign in to comment.

Accepted Answer

Nagasai Bharat
Nagasai Bharat on 7 May 2021
Hi,
From the documentation of norm and simplify you could find the usage of both these functions. norm would be used to calculate the norm of a vector/matrix but not for an expression. simpify would be used in the simplification of an algebric expression.
  1 Comment
Niklas Kurz
Niklas Kurz on 8 May 2021
well, it actually works if u were to incorporate some assumptions:
assume(phi>0);assume(the>0); assume(phi,'real'); assume(the,'real')
then, under these conditions
simplify(norm(c))
will simplify a lot (actually >0 not necessary)

Sign in to comment.

More Answers (0)

Tags

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by