DIFF

 

 Differentiate or difference.

  DIFF may be called with either numeric or symbolic arguments.

 

 

  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.

 

 

  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.

 

 

  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

 

 

      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'.

 

 

  See also GRADIENT1ZKGDQ2, DEL216NX1U2, INT, SYMVAR.