an error in new versions? triognometric function of A*t
조회 수: 2 (최근 30일)
이전 댓글 표시
Please run the following code in MATLAB R2017a
A1=simplify(A1), A2=simplify(A2)
A=[-7,2,0,-1; 1,-4,2,1; 2,-1,-6,-1; -1,-1,0,-4];
syms t, A1=(expm(A*1j*t)-expm(-A*1j*t))/(2*1j);
A2=(expm(A*1j*t)+expm(-A*1j*t))/2;
The results are different from the ones in earlier versions such as R2008a, R2011a. The results in earlier versions are consistent with the commands funm(A*t,'sin'). Obviously the results in the new versions are wrong, or at least not simplified well.
댓글 수: 0
채택된 답변
Stefan Wehmeier
2017년 8월 25일
It is a matter of taste if you prefer results in terms of exp or sin. You could do
simplify(rewrite(A1, 'sin'))
추가 답변 (0개)
참고 항목
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!