只把這個函數給你吧,你自己保存下:

function F = ztrans(varargin)

%ZTRANS Z-transform.

%? ?F = ZTRANS(f) is the Z-transform of the scalar sym f with default

%? ?independent variable n.??The default return is a function of z:

%? ?f = f(n) => F = F(z).??The Z-transform of f is defined as:

%? ?? ?F(z) = symsum(f(n)/z^n, n, 0, inf),

%? ?where n is f's symbolic variable as determined by FINDSYM.??If

%? ?f = f(z), then ZTRANS(f) returns a function of w:??F = F(w).

%

%? ?F = ZTRANS(f,w) makes F a function of the sym w instead of the

%? ?default z:??ZTRANS(f,w) <=> F(w) = symsum(f(n)/w^n, n, 0, inf).

%

%? ?F = ZTRANS(f,k,w) takes f to be a function of the sym variable k:

%? ?ZTRANS(f,k,w) <=> F(w) = symsum(f(k)/w^k, k, 0, inf).

%

%? ?Examples:

%? ?? ?syms k n w z

%? ?? ?ztrans(2^n)? ?? ?? ???returns??z/(z-2)

%? ?? ?ztrans(sin(k*n),w)? ? returns??sin(k)*w/(1-2*w*cos(k)+w^2)

%? ?? ?ztrans(cos(n*k),k,z)??returns??z*(-cos(n)+z)/(-2*z*cos(n)+z^2+1)

%? ?? ?ztrans(cos(n*k),n,w)??returns??w*(-cos(k)+w)/(-2*w*cos(k)+w^2+1)

%? ?? ?ztrans(sym('f(n+1)')) returns??z*ztrans(f(n),n,z)-f(0)*z

%

%? ?See also IZTRANS, LAPLACE, FOURIER.

%? ?Copyright 1993-2003 The MathWorks, Inc.

%? ?$Revision: 1.20.4.2 $??$Date: 2004/04/16 22:23:22 $

% Trap for errors in input first.

if nargin >= 4

error('symbolic:sym:ztrans:errmsg1','ZTRANS can take at most 3 input variables');

end

% Make f a sym and extract the variable closest to 'x'.

f = sym(varargin{1});

% Find all symbolic variables in f.

vars = [ '{' findsym(f) '}' ];

% Determine whether n is in the expression.

varcheck = maple([ vars ' intersect {n}']);

% If n is a symbolic variable, make it the default.??Otherwise

% let the variable closest to x be the variable of integration.

if isequal(varcheck,'{n}')

var = sym('n');

else

var = findsym(f,1);

end

% If var is empty, then the default is var = 'n'.

if isempty(var)

var = sym('n');

end

% determine whether f is a function of z or another variable.

z_test = strcmp(char(var),'z');

%? ?If f = f(z), return F = F(w)

if nargin == 1 & z_test == 1

n = var;

z = 'w';

end

if nargin == 1 & z_test == 0

n = var;

z = 'z';

end

if nargin == 2

n = var;

if isempty(n), n = 'n'; end;

z = sym(varargin{2});

end

if nargin == 3

n = sym(varargin{2});

z = sym(varargin{3});

end

F = maple('map','ztrans',f,n,z);

總結

以上是生活随笔為你收集整理的matlab找不到函数系统函数,求助，Matlab找不到ztrans函数的全部內容，希望文章能夠幫你解決所遇到的問題。

如果覺得生活随笔網站內容還不錯，歡迎將生活随笔推薦給好友。