This fixes the common.pyx related errors. There are a few more you'll need to address.
I've added a new argument to "go()", the initial field values for one field. This should just be an array of float64 values in the same order as fields.pxd.
A couple of problems I noticed:
sim.pyx loops over (N_x + 2) (and y and z), which is larger than what you're allocating.
fields.pyx has Field as a class, fields.pxd has it as a struct... This seems iffy.
This fixes the common.pyx related errors. There are a few more you'll need to address.
I've added a new argument to "go()", the initial field values for one field. This should just be an array of float64 values in the same order as fields.pxd.
A couple of problems I noticed: