Abstract: There is provided a code generation method. The method comprises extracting columns corresponding to the number of symbols of a codeword from a parity check matrix of an error correction code; generating a shortened parity check matrix for the error correction code on the basis of the columns corresponding to the number of symbols of the codeword; checking whether the shortened parity check matrix includes an independent nonzero syndrome for each of a single symbol error and a double error; and generating a parity check matrix for a correction of the single symbol error corresponding to the number of bits of the shortened parity check matrix and a correction of the double error corresponding to the number of bits of the shortened parity check matrix if the shortened parity check matrix includes the independent nonzero syndrome for each of the single symbol error and the double error.

Abstract: This invention discloses a process for the production of 2-methoxy-3,6-dichlorobenzoic acid which comprises reacting 2-amino-3,6-dichlorobenzoic acid with nitrous acid to form the corresponding diazonium salt, hydrolyzing the diazonium salt to form 2-hydroxy-3,6-dichlorobenzoic acid and methylating said hydroxy acid.