Re: LS fit to a plane
- To: mathgroup at smc.vnet.net
- Subject: [mg16838] Re: [mg16828] LS fit to a plane
- From: Maarten.vanderBurgt at icos.be
- Date: Thu, 1 Apr 1999 21:35:17 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Virgil,
Have a look at the following:
In[1]:= z[x_,y_]:= 3x+5y-9;
In[2]:= xyzdata =
Flatten[Table[{u,v,z[u,v]+Random[]},{u,-1,+1},{v,-1,1}],1]
Out[2]=
{{-1,-1,-16.9183},{-1,0,-11.6465},{-1,1,-6.13617},{0,-1,-13.8047},{0,
0,-8.3627},{0,1,-3.00167},{1,-1,-10.0657},{1,0,-5.43228},{1,1,-0.174832}}
In[3]:= Fit[xyzdata,{1,x,y},{x,y}]
Out[3]= -8.39366+3.17135 x+5.24602 y
The equation of the plane is z = 3 x + 5 y - 9.
In xyzdata I add some random noise to nine points in this plane.
Then I fit the leas mean square plane using the Fit[] command.
If you want more regression data have look in the package
Statistics`LinearRegression`.
regards
Maarten
___________________________________________________________________________
____
Maarten van der Burgt
R&D Department
ICOS Vision Systems
Esperantolaan 9
B-3001 Leuven
Belgium
tel. + 32 16 398220 direct + 32 16 398316 fax. + 32 16
400067
e-mail: maarten.vanderburgt at icos.be
___________________________________________________________________________
____
Virgil Stokes <virgil.stokes at neuro.ki.se> on 30-03-99 08:35:25 AM
Subject: [mg16838] [mg16828] LS fit to a plane
I would like to fit a set of 3D coordinates (each with measurement error)
to a plane; i.e.
find the parameters A,B,C,D in
Ax + By + Cz + D = 0
for a set of (x,y,z) measurements.
-- V. Stokes