Index of Memorial Resolutions and Biographical Sketches

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Robert Todd Gregory was born on March 19, 1920, in Owensboro, Kentucky, to devout Baptist parents. He was the third of five sons, and grew up in Fredericksburg, Virginia, where his father was a Doctor of Veterinary Medicine. Gregory graduated from James Monroe High School in Fredericksburg in 1937. At graduation, he received the Kiwanis Cup, which was presented to the student who had contributed the most to the school during his or her high school years. In 1937-38, he attended Georgetown College, Georgetown, Kentucky, prior to obtaining an appointment to the U.S. Naval Academy. After being commissioned an ensign in 1942, he served his country in the South Pacific. After World War II, he resigned from the navy to do graduate work in mathematics, receiving a master's degree from Iowa State University in 1948, and a PhD from the University of Illinois in 1955.

In 1944, Gregory married Margaret Bentzinger in Ottumwa, Iowa. They had two children and four grandchildren. As a youth, he was baptized and joined the Baptist Church; later he was ordained a deacon in the University Baptist Church in Austin, Texas. He faithfully tithed his income from the time he had his first paper route until his death. When he moved to Knoxville, Tennessee, he joined Church Street United Methodist Church and the Pathfinders Class where he often served as a teacher. He was a member of the administrative board, and twice was a delegate to the Holston Annual Conference. In 1981, he was a delegate to the World Methodist Conference in Honolulu, Hawaii. As an ardent photographer, he enjoyed recording the faces of people he met during his worldwide travels as well as those of new members of his church each Sunday.

Gregory owned a Cessna during the time his daughter Rosalie was attending Westminster Choir College in Princeton. He flew from Austin to hear the choir sing the Messiah one December, and as the two of them flew back to Austin, he taught Rosalie "how to navigate, finding the omni ranges and turning the radio to the right frequency on each leg of the trip."

Robert T. Gregory passed away Wednesday, November 14, 1984, in Knoxville, Tennessee, at the age of 64. He died from complications following gall bladder surgery. Memorial services were held at the Church Street United Methodist Church in Knoxville. He was survived by his wife, Margaret, of Donnellson, Iowa; son, Carl, of Austin, Texas; daughter, Rosalie, of Los Angeles, California; brother, Howard E. Gregory, of Fredricksburg, Virginia; and grandchildren, Jason Mills, Jeanne-Jo Gregory, Brian Gregory, and Alan Gregory.

Professional Appointments

Gregory served as a professional naval officer during 1942-46, first as a torpedo officer on the destroyer USS Fletcher and then as a naval aviator. Between 1946 and 1948, he studied at Iowa State University, obtaining a master's degree in 1948. He then started his mathematical career at the U.S. Naval Weapons Laboratory, Dahlgreen, Virginia, as a mathematician and scientific programmer. In 1949, he took a position as an instructor in mathematics at Florida State University. Upon leaving there in 1950, he attended the University of Illinois in Urbana, and worked as a research assistant and then research associate in the Digital Computer Laboratory. His PhD supervisor was Professor Abraham Taub. After obtaining his PhD in 1955, he took a position as assistant professor of mathematics at the University of California, Santa Barbara.

In 1959, Robert joined the faculty of The University of Texas in Austin, as an associate professor of mathematics. He was the associate director of the Computation Center (1959-66) and then the associate director of the Center for Numerical Analysis (1970-75). He became a full professor in 1963. From 1966 to 1968, Gregory was acting chairman of the newly-established computer sciences department. In 1968, he became a professor of computer sciences.

Dr. Gregory was a consultant for the U.S. Naval Air Missile Test Center (1956), for the Ramo-Woolridge Corporation, later Space Technology Laboratories, (1956-58), and for the Applied Mathematics Division of the Argonne National Laboratory (1962-63). He held visiting research and teaching positions at the Digital Computer Laboratory, University of Illinois (1960); the Computation Center, Stanford University (1963); the Computer Science Laboratory of the Graduate Research Center of the Southwest (1964, 1965); the Computer Center, University of California, Berkeley (1964, 1965, 1966); Fides Rechenzentrum, Switzerland (1969); the Computer Center, University of Lund, Sweden (1969); and the University of Bonn, West Germany (1973).

While at The University of Texas at Austin, Professor Gregory served on the Dean's Selection Committee for the College of Natural Sciences, the Degree and Course Committee, and the Special Advisory Committee for Students in the Health Services.

Gregory left Austin in 1975 to become the head of the computer science department at the University of Tennessee at Knoxville. In 1983, Professor Gregory retired as professor emeritus in both computer science and mathematics at the University of Tennessee to devote more time to writing. His last book, Methods and Applications of Error Free Computation, coauthored with E. V. Krishnamurthy, was published two months before he died. The book later was translated into Russian. He was scheduled to lecture in China in the fall of 1984 and to visit The University of Texas at Austin in the spring of 1985.

Honors, Awards, and Activities in Professional Organizations

Gregory was listed in Who's Who in America, American Men and Women of Science, World Who's Who in Science, and Who's Who in the World. For four years he was a member of the panel of visiting scientists for the Visiting Scientists Lectureship Program of the Society for Industrial and Applied Mathematics (SIAM). He was also a visiting lecturer for the Visiting Lecturers Program of the Texas Academy of Science and the Association for Computing Machinery.

He was a member of the American Mathematical Society, the Mathematical Association of America, the Society for Industrial Applied Mathematics, the Association for Computing Machinery, and Sigma Xi. He was a member of the editorial board for the SIAM Journal on Applied Mathematics. Gregory was a reviewer for Computing Reviews and Mathematical Reviews.

Invited Lectures Abroad

Dr. Gregory gave invited lectures in Sweden, Norway, Denmark, Germany, Switzerland, Italy, Kuwait, India, and Australia.

Teaching and Research

Professor Gregory regularly taught both undergraduate and graduate courses in mathematics and computer sciences. He supervised 8 PhD students and 26 MA/MS students. He served on other PhD and MA degree committees, in mathematics, computer sciences, engineering, psychology, and educational psychology. He was the coprincipal investigator with Dr. David M. Young on numerous grants from the Army Research Office (1962-74) on basic research in numerical analysis and from the National Science Foundation (1962-71) on numerical methods for differential and algebraic equations. He was involved in similar activities when he was at the University of Tennessee at Knoxville.

The Dr. Robert Todd Gregory Memorial Fund

The computer science departments and the mathematics departments of the University of Tennessee at Knoxville and The University of Texas at Austin established a fund to support a lecture series in memory of Professor Robert Todd Gregory. A large portion of Dr. Gregory's career was spent at these two institutions, where he made significant contributions to his field of numerical linear algebra and to the life and success of each department. The fund supported lectures on numerical linear algebra and topics in related areas for approximately a decade after his death.


A close colleague at UT Austin, Professor David M. Young, wrote,

"Professor Gregory had a long and distinguished career and made many outstanding contributions in numerical analysis. His publications included over 30 research papers and reports as well as 5 books, including a two-volume treatment of numerical mathematics, which he and I coauthored. He was one of the world's leading experts in error-free computation, an important area in mathematics as well as in computer science. He also made contributions in matrix algebra and residue arithmetic."

Young also praised Gregory's value to numerical analysis and to the University. Young said that Gregory

"was an ideal faculty member, with an extremely pleasant personality and the ability to get along well with others. He was genuinely interested in students and was an excellent classroom teacher."

Robert Gregory was known for his integrity, his concern for the hungry, his unswerving faith, his devotion as a husband and father, and his real sense of calling in his profession. His daughter paid him perhaps the highest tribute:

"You lived your values, consistently dedicated to honesty and truth and peace — to fairness and equality for all people."


Larry R. Faulkner, President
The University of Texas at Austin


John R. Durbin, Secretary
The General Faculty

This memorial resolution was prepared by a special committee consisting of Professors David M. Young (chair), E. W. Cheney, and David R. Kincaid. The committee wishes to acknowledge the valuable assistance of undergraduate students Tom Dang and Cheng Hao Masa Lin.

Copies of the bibliography are available from the Office of the General Faculty upon request.