Jacob T. Schwartz, a mathematician and computer scientist who did seminal research in fields as diverse as molecular biology and robotics, died Monday at his home in Manhattan. He was 79.

He died in his sleep of liver cancer, his wife, Diana, said. He was chairman of the computer science department at New York University, which he founded, from 1964 to 1980.

During a career that also included 42 years as a professor at the Courant Institute for Mathematical Sciences at the university, Dr. Schwartz wrote more than a dozen books and more than 100 scientific papers and research reports. At his death Dr. Schwartz was actively working on research in both molecular biology and logic.

Throughout his life, Dr. Schwartz, who was known as Jack, moved from one scientific field to the next. He was not a dilettante, but mastered each field in turn and then made significant contributions.