Force NN to find u within an inter-range

[ciri1998]

Good morning, I was wondering if it would be possible to force the NN to find the solution within 0, 1 for u[0] and between 2 and 3 for u[1] for example

[benmoseley]

One way might be to use hard constraints - see here for an example: https://github.com/benmoseley/FBPINNs/blob/main/examples/2.%20Using%20hard%20constraints%20-%201D%20harmonic%20oscillator.ipynb
For example, if you want to restrict the solution to the range 0-1, you could pass the output of the network through a sigmoid function.