PASADENA, Calif.-John Todd, one of the pioneers of numerical analysis, died Thursday, June 21, at his home in Pasadena, California. He was 96.

Todd's legacy and impact on modern-day mathematics can be seen in his contributions to analysis, linear algebra, and computation. His work was a precursor to and helped shape the foundation for today's computer science field. An emeritus professor at the California Institute of Technology, Todd developed the first undergraduate courses at Caltech in numerical analysis and numerical algebra, which play a key role in scientific computing.

Born in Ireland in 1911, Todd grew up near Belfast. After earning his BSc degree from Queen's University in 1931, he went to St. John's College at Cambridge University for graduate studies under renowned mathematicians J.E. Littlewood and G.H. Hardy.

Subsequently, Todd went to work at King's College in London, where he soon met his intellectual and romantic match, Olga Taussky, a matrix and number theorist. They wed in 1938.

In 1939, when Britain declared war on Germany, Todd found an opening with the British Admiralty, which assigned him to Portsmouth to help develop methods for degaussing-or demagnetizing-ships to keep them from being blown up by enemy torpedoes.

Referred to by some as the "Savior of Oberwolfach," one of Todd's most stellar achievements was his salvation of the Mathematical Research Institute at Oberwolfach in Germany. Near the war's end, Todd and his colleagues went to investigate rumors that mathematicians were being held as prisoners of war in Germany's Black Forest. What they found was the Mathematical Research Institute at Oberwolfach, where the University of Freiburg was protecting the mathematicians. Todd claimed the building for the Admiralty and prevented Moroccan troops from destroying the institute and its work. In his Caltech oral history, Todd recalls the incident as "probably the best thing I ever did for mathematics."

In 1945, with peace restored, Todd returned to teaching at King's, developing a specialty in numerical analysis. In 1947, he and Olga came to the United States to help establish the National Applied Mathematical Laboratories at UCLA, part of the National Bureau of Standards. They later moved to the NBS headquarters in Washington, D.C., where they helped launch the field of high-speed computer programming and analysis and also became U.S. citizens. Todd was chief of the computation laboratory and later headed the numerical analysis section, while Olga served as a consultant.

In 1956, the couple received job offers from Caltech, which was just entering computer science. The following year, they arrived at the Institute, where Todd developed and taught courses in mathematics. As a faculty research associate, Olga Taussky-Todd also broke new ground-she was the first woman to receive a formal Caltech teaching appointment, and, in 1971, a full professorship. She remained active in research until her death in 1995.

Thomas A. Tombrello, chair of the Division of Physics, Mathematics, and Astronomy and William R. Kenan, Jr. Professor of Physics at Caltech says, "Jack and his wife Olga were among the pioneers who made us what we are in teaching and research in mathematics. Our sense of collegiality and common purpose are a tribute to them."

"It was a terrific day for the mathematics department when we succeeded in attracting Jack and Olga to come to Caltech," says Gary Lorden, professor of mathematics.

"Not only did we gain eminent scholars, but wonderful colleagues and teachers. They made a remarkably generous commitment to the future of Caltech and the mathematics department, and their legacy also includes the inspiring stories of their lives and careers-Olga, as one of the very first women to make a mark in 20th-century mathematics, and Jack as a pioneer in numerical analysis and computing.

"These two remarkable people will always be remembered with great affection and regard by mathematicians and the Caltech community."

Written by Deborah Williams-Hedges