Hello,
I would like to linearize a differential equation around a equilibrium position. The description of the steps that I have carried out are :
Equation
eq = 1/2 g l m Cos[?[t]] == J (?^??)[t]
Equation around the equilibrium position can be re-written as :
eqAe = Replace[eq, ?[ t] -> (?e &) + ??[t], ?]
Change of variables
eqLi = Replace[eq, {D[??[t], {t, 2}] -> ??pp, D[??[t], t] -> ??p, ??[t] -> ??}, ?]
Linearization
eqLi2 = Series[eqLi[[1]], {{??pp, ??p, ??}, {0, 0, 0}, 1}] ==
Series[eqLi[[2]], {{??pp, ??p, ??}, {0, 0, 0}, 1}]
Change of variables
eqLi3 = Replace[eq, ??pp -> {D[??[t], {t, 2}], ??p -> D[??[t], t], ?? -> ??[t]}, ?]
Currently, I try to transform a code that I have done on Maple and which works to Mathematica. However, I have still some blocking points.
Can anyone help me to obtain to correct my code ? I send the .nb in copy
Thanks a lot for your help
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