A method for designing a computer program for finding a low-complexity coder for constrained block codes for application to timing recovery or error control in data recording systems. The method includes (1) decomposing an input set of candidate codewords into simple subsets of codewords, (2) providing, for each simple subset of codewords, a respective subset of datawords, and (3) filling in certain coordinates in the datawords by values of certain coordinates in the codewords.