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subroutine ext10f(n, t, y, ydot)
c external fonction for ode
c input variables n, t, y
c n = dimension of state vector y
c t = time
c y = state variable
c output variable = ydot
c
c external routine must
c load ydot(1) with d/dt ( y(1)(t) )
c ydot(2) with d/dt ( y(2)(t) )
c ...
c i.e. ydot vector of derivative of state y
c
c With dynamic link:
c link('ext10f.o','ext10f')
c
c passing a parameter to ext10f routine by a list:
c -->param=[0.04,10000,3d+7];
c -->y=ode([1;0;0],0,[0.4,4],list('ext10f',param))
c param is retrieved in ext10f by:
c param(1)=y(n+1) , param(2)=y(n+2) etc
c with this calling sequence y is a n+np vector
c where np=dimension of scilab variable param
c
c Copyright INRIA
double precision t, y, ydot, param
dimension y(3), ydot(3),param(3)
param(1)=y(n+1)
param(2)=y(n+2)
param(3)=y(n+3)
ydot(1) = -param(1)*y(1) + param(2)*y(2)*y(3)
ydot(3) = param(3)*y(2)*y(2)
ydot(2) = -ydot(1) - ydot(3)
end
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