Brill-Noether Algorithm, Weierstrass-SG and AG-codes: Implementation of the Brill-Noether algorithm for solving the Riemann-Roch problem and applications in Algebraic Geometry codes. The computation of Weierstrass semigroups is also implemented. The procedures are intended only for plane (singular) curves defined over a prime field of positive characteristic. For more information about the library see the end of the file brnoeth.lib.