Scilab Website | Contribute with GitLab | Mailing list archives | ATOMS toolboxes
Scilab Online Help
6.0.1 - English

Change language to:
Français - 日本語 - Português - Русский

Please note that the recommended version of Scilab is 2024.0.0. This page might be outdated.
See the recommended documentation of this function

Scilab Help >> Differential calculus, Integration > diff

diff

Difference and discrete derivative

Syntax

y=diff(x)
y=diff(x [,n [,dim]])

Arguments

x

vector or matrix (real, complex, sparse or polynomial)

n

integer the order of differentiation

dim

integer or character string with values "r","c" and "*"

y

scalar or vector/matrix

Description

y=diff(x) compute the difference function y=x(2:$)-x(1:$-1)

diff(x,n,dim) is the nth difference function along dimension dim.

diff(x,n,"*") is equivalent to diff(x(:),n).

Default value for n is 1. Default value for dim is "*".

dim='r' is equivalent to dim=1 and dim='c' is equivalent to dim=2.

Examples

v=(1:8)^3;
diff(v)
diff(v,3)

A=[(1:8)^2
   (1:8)^3
   (1:8)^4];

diff(A,3,2)

//approximate differentiation
step=0.001
t=0:step:10;
y=sin(t);
dy=diff(sin(t))/step; //approximate differentiation of sine function
norm(dy-cos(t(1:$-1)),%inf)

See also

  • interp — cubic spline evaluation function
  • interp2d — bicubic spline (2d) evaluation function
  • splin — cubic spline interpolation
  • eval_cshep2d — bidimensional cubic shepard interpolation evaluation
  • numderivative — approximate derivatives of a function (Jacobian or Hessian)
Report an issue
<< dassl Differential calculus, Integration impl >>

Copyright (c) 2022-2023 (Dassault Systèmes)
Copyright (c) 2017-2022 (ESI Group)
Copyright (c) 2011-2017 (Scilab Enterprises)
Copyright (c) 1989-2012 (INRIA)
Copyright (c) 1989-2007 (ENPC)
with contributors
Last updated:
Mon Feb 12 19:26:46 CET 2018