Charles W. Johnson discusses his career in computing and mathematics with particular attention to his role as cofounder and chairman of IMSL, one of the leading commercial suppliers of mathematical software libraries. Johnson received an undergraduate degree in engineering from the University of Wisconsin, Madison and a master's degree from MIT, graduating in 1955, where he was exposed to the Whirlwind computer. After a two year spell working as a computer center manager for the Army Corps of Engineers, and a brief interregnum with his father’s construction company, he went to work for IBM in Milwaukee as a representative of its Applied Science department. In 1970 he became co-founder of IMSL (along with his IBM colleague Ed Battiste, and its main investor). Although Johnson’s role with IMSL was that of chairman and financial backer rather than employee, for most of the next thirty five years IMSL was his main preoccupation. He discusses its founding, development and growth, sales strategies, and its key staff members. Johnson also discusses the firm’s change of direction in the 1990s, as it merged with Precision Visuals Incorporated, changed its senior management team and eventually relocated to California. Johnson concludes the interview with a review of his activities as an investor and philanthropist, including involvement with MIT and the Mayo Clinic.
Whirlwind computer; Software library; IMSL (International Mathematics and Statistics Library); Numerical Algorithms Group (NAG); MATLAB (Programming language); SPSS (Software); SAS (Software)
Society for Industrial and Applied Mathematics (SIAM) oral history collection