# Determine the coefficients in symbolic

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Tobias Dehn Nielsen on 24 Nov 2022
Commented: Paul on 25 Nov 2022
On is dependent of In, On_1 and In_1. Is there a way to determine the coefficients multiplied on In, On_1 and In_1. On is of filetype sym.

Torsten on 24 Nov 2022
I don't know why the coefficients appear in the wrong order.
syms In In_1 On_1
On = 91/100*In-7/8*In_1+1/2*On_1;
coeffs(On,[In In_1 On_1])
ans =
Paul on 25 Nov 2022
I'm not sure it's a bug.
The single output form for a univariate polynomial returns coefficients from lowest to highest order
syms x
c = coeffs([2*x^2 + 3*x + 1])
c =
But the two output form returns from highest to lowest
[c,t] = coeffs([2*x^2 + 3*x + 1])
c =
t =
Seems odd, but both of those cases are documented behavior.
When using the second input argument, vars, I don't see anything in the doc that says that ordering of c corresponds to the order in vars. The doc has a bunch of examples, but it doesn't really explain the process for how it orders c and t.