Calculate vector norm in Simulink?

Is there a block that finds the norm of a vector in simulink? I haven't found the equivalent to norm(v) from MATLAB.

Thanks!

Answer 1

[Jon]

You can use the dot product block (with the same vector wired to both inputs) followed by a square root. Both are under the Math Operations library. I think the previously suggested abs block computes the absolute values of each element of the input vector.

Answer 2

[Youssef Khmou]

hi, it does exist, its called "abs" , open Simulink library and go to :"Math operations" block , its the first on the list, with notation u : ABS

[Jon]

As noted in my alternative answer, I don't this this gives you what you want. As far as I can tell abs gives the element wise absolute values, not the norm

[Steven Crews]

Agreed. This is not the correct answer.

Answer 3

[Joshua]

Thanks!

Answer 4

[Youssef Khmou]

hi, if the first answer does not work, you can use other ways, like :

1) go to " User Defined Functions" in Simulink Block .

2) choose "f(u)" FCN, add it to your file , right click on it you will find the default value :

 sin(u(1)*exp(2.3*(-u(2))))

change it to

"norm(u)"

[Jon]

The user defined function f(u) does not accept norm(u). From the documentation it only seems to accept the following: abs, acos, asin, atan, atan2, ceil, cos, cosh, exp, fabs, floor, hypot, ln, log, log10, pow, power, rem, sgn, sin, sinh, sqrt, tan, and tanh.

[Youssef Khmou]

ok, choose the "Embeded function" instead

[Jon]

I couldn't find and "Embeded function" Do you mean the Interpreted MATLAB Fcn under User Defined Functions? The Interpreted MATLAB Fcn works, but I would guess that the dot product block, followed by the sqrt block is faster, because it doesn't need to be interpreted.

[Youssef Khmou]

yes the Fcn component...

Answer 5

[DEBASISH MISHRA]

Hi,

You may direct use matrix 1-norms from dsp tool box.

Thanks