Mathematics professor Dan Sweet, 61, died Sunday at Georgetown Hospital after suffering a stroke Nov. 10.

Sweet, of Laurel, was known for his passion for teaching and sharp-witted sense of humor.

For example, university mathematics professor and longtime friend John Benedetto, remembered visiting Sweet at his home after he had major heart surgery a few years ago.

"He pointed to his chest after surgery and said, 'Boy, I had a go through this to get a visit?'" Benedetto recalled. "His sense of humor, probably in the classroom you didn't see it, but he could've been a standup comic."

Benedetto added Sweet's tough demeanor belied his sensitivity to people's needs. "He looked tougher than he was."

Gene Harrington, a 1992 journalism alumnus, knew Sweet since he was 7 years old as a neighbor and as "a second dad." Harrington, now 35, struggled with the journalism school's minimal math requirements. He attributed his passing MATH 110: Elementary Mathematical Models to Sweet's informal math tutoring.

"Although he was a genius in his field, he wasn't a math wonk," he said. "He was just a regular guy blessed with an incredible intellect. He was able to communicate his genius and that was what made him such an effective teacher and so fun to be around."

Born in Passaic, N.J., Sweet began his 35-year career with the university in 1969 after earning his doctorate in mathematics at Brown University, working for a year at the University of California, Los Angeles, and marrying his wife, Karen.

"His passion was teaching at the University of Maryland," Karen said. "He never thought of doing anything else. He could of gone into the industry, but he received so much satisfaction from teaching."

He won the Dean's Excellence in Teaching Award in 1989, given each year to one of the 250 faculty in the computer, mathematical and physical sciences college. While Sweet did publish scholarly research, math department Chairman Patrick Fitzpatrick said Sweet was a teacher first and a researcher second.

"He published lots of research articles, but he chose to devote the majority of his time to his students," he said.

Sweet presented complex math concepts with clarity and simplicity and was, in the words of math department undergraduate chair Denny Gulick, "the king" of MATH 410 and 411: Advanced Calculus I and II.

The two courses are among math majors' most challenging, and he recalled students who put off taking the courses if Sweet wasn't teaching them, Fitzpatrick said.

Sweet often taught more than 200 students each semester. While Sweet's family was unable to speak with him after the stroke, Karen took solace in the fact that her husband collapsed after teaching two of his classes.

"So the last thing he did was something that he loved," she said.

He is survived by his wife Karen, 60, and sons Daniel, 33, of Rockville, and James, 32, of Chesapeake Beach, Md.

Donations may be sent to 11801 Rockville Pike, Condo #1403, Rockville, Md., 20852 for the Daniel Sweet Memorial Mathematics Scholarship Fund.

- By senior staff writer Jeremy Hsieh