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

Change language to:
Français - 日本語 - Português

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 This page might be outdated.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 manual >> Graphics Library > 2d_plot > fchamp

fchamp

direction field of a 2D first order ODE

Calling Sequence

fchamp(f,t,xr,yr,[arfact,rect,strf])
fchamp(f,t,xr,yr,<opt_args>)

Arguments

f

An external (function or character string) or a list which describes the ODE.

-

It can be a function name f, where f is supposed to be a function of type y=f(t,xy [p1,..pn]). f returns a column vector of size 2, y, which gives the value of the direction field f at point xy=[x,y] and at time t.

-

It can also be an object of type list, list(f,P1,..Pn) where f is a function of type y=f(t,xy,p1,..pn) and Pi gives the value of the parameter pi.

t

The selected time.

xr,yr

Two row vectors of size n1 and n2 which define the grid on which the direction field is computed.

<opt_args>

This represents a sequence of statements key1=value1,key2=value2, ... where key1, key2,... can be one of the following: arfact, rect, strf (see below).

arfact,rect,strf

Optional arguments, see champ.

Description

fchamp is used to draw the direction field of a 2D first order ODE defined by the external function f. Note that if the ODE is autonomous, argument t is useless, but it must be given.

Enter the command fchamp() to see a demo.

Examples

deff("[xdot] = derpol(t,x)",..
        ["xd1 = x(2)";..
         "xd2 = -x(1) + (1 - x(1)**2)*x(2)";..
         "xdot = [ xd1 ; xd2 ]"])
xf= -1:0.1:1;
yf= -1:0.1:1;
fchamp(derpol,0,xf,yf)
clf()
fchamp(derpol,0,xf,yf,1,[-2,-2,2,2],"011")

See Also

Authors

J.Ph.C.

<< errbar 2d_plot fcontour2d >>

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:
Wed Jan 26 16:23:43 CET 2011