** Differentiate or difference. **

** DIFF may be called with either numeric or symbolic arguments. **

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** For a numeric vector argument, DIFF computes differences. **

** DIFF(X), for a vector X, is [X(2)-X(1) X(3)-X(2) ... X(n)-X(n-1)]. **

** DIFF(X), for a matrix X, is the matrix of column differences, **

** [X(2:n,:) - X(1:n-1,:)]. **

** DIFF(X,n) is the n-th difference function. **

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** For a symbolic (string) argument, DIFF uses the Maple Symbolic Toolbox **

** to compute derivatives. **

** DIFF(S) differentiates S with respect to its free variable. **

** DIFF(S,'v') differentiates S with respect to 'v'. **

** DIFF(S,n) and DIFF(S,'v',n) differentiate S n times. **

** DIFF, with no arguments, differentiates the previous expression. **

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** Examples; **

** With numeric arguments: **

** h = .001; x = 0:h:pi; **

** diff(sin(x.^2))/h is an approximation to 2*cos(x.^2).*x **

** diff((1:10).^2) is 3:2:19 **

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** With symbolic arguments and the Maple Symbolic Toolbox: **

** diff('sin(x^2)') is '2*cos(x^2)*x' **

** diff sin(x^2) is also '2*cos(x^2)*x' **

** diff('t^6',6) is '720'. **

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** See also GRADIENT , DEL2 , INT, SYMVAR. **

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