Question: Get a numerical value of dsolve solution and use it in later calculus

Hello,

I'm new to Maple and I'm struggling with dsolve output.

I solve this equation
 

ode:=diff(y(t),t)=-(4/3)*(a/eta)*(y(t)^3+1):
lambdaE:=dsolve({ode,y(0)=1},y(t),numeric,method=classical[rk4],parameters=[a,eta],output=listprocedure):
lambdaE(parameters=[theta[5,1],eta0]):

tCompute:=20*(lambda-~1)/(50/60): #vector with times I need 
# lambda is a 371 lines column vector

Then I need the value of the solution at each time to compute components of a matrix

J:=Matrix(371,5):
for i from 1 to 371 do
	J[i,1]:=2*(lambda[i]-1/lambda[i]^2);
	J[i,2]:=4*(lambda[i]^2-2/lambda[i]-3)*(lambda[i]-1/lambda[i]^2);
	J[i,3]:=6*(lambda[i]^2-2/lambda[i]-3)^2*(lambda[i]-1/lambda[i]^2);
	J[i,4]:=2*(1-1/lambda[i]^3);
	J[i,5]:=2*(lambdaE(tCompute[i])^2/lambda[i]-(1/lambdaE(tCompute[i])*lambda[i])); #here is where I need the value
end do;

However the output in the 5th column of J is something with y(t) and t inside

1.997498088*[t = 0.0300605520000000, y(t) = 0.999829465489350]^2 - 2.002505046/([t = 0.0300605520000000, y(t) = 0.999829465489350])

Would you have a solution to get only the numerical value ?

Thanks a lot in advance

Manon