The porewater pressure parameter from a CPT is denoted by $u$ or $u_2$ (u subscript 2). $u_2$ (u subscript 2) seems to be used more often than $u$, which lets related parameters be unambiguously referred to by other subscripts like $u_1$. For example, this page from the NZ Geotechnical Society refers to the porewater pressure as $u_2$. Therefore, I propose changing the variable u to u2 everywhere in this repo to reduce the chance of confusion.
