home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Amiga Format CD 46
/
Amiga Format CD46 (1999-10-20)(Future Publishing)(GB)[!][issue 1999-12].iso
/
-in_the_mag-
/
reader_requests
/
scilab
/
man
/
man-part2
/
cat4
/
chaintest.4
< prev
next >
Wrap
Text File
|
1999-09-16
|
1KB
|
67 lines
chaintest(1) Scilab Function chaintest(1)
NAME
chaintest - a three-species food chain model
CALLING SEQUENCE
chaintest([f_l,b1,odem,xdim,npts])
[xdot]=chain(t,x)
[z1]=ch_f1(u)
[z2]=ch_f2(u)
PARAMETERS
f_l : the name of the macro which code the three-species food chain model
(default value chain).
odem,xdim,npts
: are optional arguments. Their meaning and syntax can be found in the
portr3d help
DESCRIPTION
A call to the function chaintest() will interactively display a phase por-
trait of a three-species food chain model given by:
ff1= f1(x(1))
ff2= f2(x(2))
xdot1= x(1)*(1-x(1)) - ff1*x(2)
xdot2= ff1*x(2) - ff2*x(3) - 0.4*x(2)
xdot3= ff2*x(3) - 0.01*x(3)
and
f1(u)=5*u/(1+b1*u)
f2(u)z2=0.1*u/(1+2*u)
The default value for b1 is 3.0.
The Scilab macros chain(t,x),f1(u),f2(u) code the dynamical system
SEE ALSO
portr3d,ode