how to show this

if the

1

G(s) = --------------------------------------------------------------

s^6 + 4 s^5 + 3 s^4 + 3.553e-15 s^3 + s^2 + 3 s

how to make in matlab

1

G(s) = ---------------------------------------------------------------

s^6 + 4 s^5 + 3 s^4 + s^2 + 3 s

[Walter Roberson]

Question was about how to discard a small coefficient in a transfer function.

[Stephen23]

Original question by Firas Romaneh retrieved from Bing Cache:

http://web.archive.org/web/20210613045003/https://cc.bingj.com/cache.aspx?q=www.mathworks.com%2Fmatlabcentral%2Fanswers%2F854845&d=3178831481536&mkt=en-WW&setlang=de-DE&w=I702SF5mcswHsnYM374sZjU1BaoEpFua

http://web.archive.org/web/20210613045930/https://www.mathworks.com/matlabcentral/answers/854845-0000000000000000000000000000

how to show this

if the

1

G(s) = --------------------------------------------------------------

s^6 + 4 s^5 + 3 s^4 + 3.553e-15 s^3 + s^2 + 3 s

how to make in matlab

1

G(s) = ---------------------------------------------------------------

s^6 + 4 s^5 + 3 s^4 + s^2 + 3 s

[Rena Berman]

(Answers Dev) Restored edit

Answer 1

[Sulaymon Eshkabilov]

It is quite simple and straightforward:

G = tf(1, [1 4 3 0 1 3 0])

Answer 2

[Walter Roberson]

G = tf([1], [1, 4, 3, 3.553e-15, 1, 1, 0])

G =
 
                        1
  ---------------------------------------------
  s^6 + 4 s^5 + 3 s^4 + 3.553e-15 s^3 + s^2 + s
 
Continuous-time transfer function.

N = cellfun(@discardsmall, G.Numer, 'uniform', 0);
D = cellfun(@discardsmall, G.Denom, 'uniform', 0);
G = tf(N, D, 'IODelay', G.IODelay)

G =
 
                1
  -----------------------------
  s^6 + 4 s^5 + 3 s^4 + s^2 + s
 
Continuous-time transfer function.

function V = discardsmall(V)
   V(abs(V)<1e-10) = 0;
end

Using a function as a helper is the easiest way because for the general case we cannot assume that the input transfer function does not have an array of transfers. G.Numer and G.Denom are cell arrays of vectors, not plain vectors.