求助Matlab的dirac函數

dirac就是數學意義上的delta 函數 也就是f(x)=0 others inf x=0; 妳用的是matlab 2009吧 看了下面的解釋，相信妳會明白 MuPAD Engine Replaces Maple Engine The default Symbolic Math Toolbox engine is now the MuPAD engine. For more information, see the MuPAD in Symbolic Math Toolbox chapter in the Symbolic Math Toolbox User's Guide. Compatibility Considerations The new engine causes many computed results to differ from those returned by previous versions of Symbolic Math Toolbox software. General Differences. Many computations return in a permuted order (such as a + b instead of b + a). Some computations return in a different, mathematically equivalent form (such as (cos(x))^2 instead of 1 - (sin(x))^2). diff(dirac(t)) returns dirac(t,1) instead of dirac(1,t).