me hidden parameters used in dimensions specifications need to be determined based on the input array size. This is a harder problem because f2py has to solve the inverse problem: find a parameter `p` such that `upper(p) - lower(p) + 1` equals to the size of input array. In the case when this equation cannot be solved (e.g. because the input array size is wrong), raise an error before calling the Fortran function (that otherwise would likely crash Python process when the size of input arrays is wrong). f2py currently supports this case only when the equation is linear with respect to unknown parameter. z