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Hello, Here is one of my test examples for stiff ode solvers (attached). I tried many lsoda based solvers in different software and they usually can solve this problem with their default parameter values (accuracy etc.). By using ode() from...

Hello, Here is one of my test examples for stiff ode solvers (see the code below). I tried many lsoda based solvers in different software and they usually can solve this particular problem with their default parameter values (accuracy etc...

Hello, I tried the example from the help of bvpshoot. Just slightly changed the code and got two different results. I think this must be a bug here, or I am doing something wrong. Please take a look at this...

Hello, This one is also one of my standard examples (chemical reactor) of two point boundary problem. I tried the three functions (bvptwp(), bvpcol(), bvpshoot()) with the default parameters and only bvpshoot() gave the results. Many other examples gave me...

Dear Thomas, Thank you very much for your prompt response. I am sorry for this inconvenience, and I will do as you said regarding the message and the code. I will resend it again this moment. Best Regards, Radovan On...

Hello, I just tried the help example about bvshoot() Example 2 - initial condition is a function of the unknown x ## tubular reactor with axial dispersion using both examples 1. by using yini() function and 2. by using bound() function. I...

I found out that if I define the function this way (use absolute value of y[1]) then the result will be correct and both solvers will work. Could someone try to explain this to me please. Best Regards, Radovan...

Also, guessing values will also help as well (not using the absolute value of y[1]). I just gave here these rather poor guess values: -first state variable given 1, and second state variable given 0 xguess <- seq(0,1...