作业帮求助Matlab的dirac函数
来源：学生作业帮 编辑：作业帮 分类：综合作业 时间：2024/05/16 08:04:31
求助Matlab的dirac函数
syms i0 i1 t i0 = cos(20*pi*t); i1 = i0*0.1*t; I0 = fourier(i0); I1 = fourier(i1); 运行后得到 I0 = pi*(dirac(w+20*pi)+dirac(w-20*pi)) I1 =1/10*i*pi*(dirac(1,w+20*pi)+dirac(1,w-20*pi)) I0的意思很好理解,I1中dirac(1,w+20*pi)是什么意思呢?单独提出来ans=dirac(1,w+20*pi),提示too many input arguments dirac的函数定义里面,也没有这种用法啊
syms i0 i1 t i0 = cos(20*pi*t); i1 = i0*0.1*t; I0 = fourier(i0); I1 = fourier(i1); 运行后得到 I0 = pi*(dirac(w+20*pi)+dirac(w-20*pi)) I1 =1/10*i*pi*(dirac(1,w+20*pi)+dirac(1,w-20*pi)) I0的意思很好理解,I1中dirac(1,w+20*pi)是什么意思呢?单独提出来ans=dirac(1,w+20*pi),提示too many input arguments dirac的函数定义里面,也没有这种用法啊
dirac就是数学意义上的delta 函数 也就是f(x)=0 others inf x=0; 你用的是matlab 2009吧 看了下面的解释,相信你会明白 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).