Issues in examples

[pmli]

• examples/1_basic_tutorial.ipynb:
  • I got x.shape == (400,) instead of x.shape == (401,)
  • in section 1.2 Finite Difference: Second Order, I suppose that second_order should be called instead of first_order
• examples/2a_optimizing_parameters_with_dxdt_known.ipynb:
  • same issue with simdt as in #13
  • removing simdt and replacing dt = 0.1 by dt = 0.01 makes things work, but the generated data looks very different compared to the pre-generated figures
  • similar issue with 1.2 Finite Difference: Second Order as above
• examples/2b_optimizing_parameters_with_dxdt_unknown.ipynb:
  • similar issues as for the 2a example

(This is related to my JOSS review: https://github.com/openjournals/joss-reviews/issues/4078)

[florisvb]

all issues fixed in latest push.

[pmli]

There is an issue in the first example (it runs fine on my machine):